Indonesia Conference Directory

Corresponding Author
Hani Kurniawati

Institutions
(a) Departemen Fisika Fakultas Matematika dan Ilmu Pengetahuan Alam, Institut Teknologi Bandung,
Jl. Ganesha no. 10 Bandung, Indonesia, 40132
*hanikurniawati[at]students.itb.ac.id
*inge[at]fi.itb.ac.id

Abstract
This paper report the results of experimental study for electrofreezing of a salt hydrate-based phase change material CaCl2.6H2O to reduce the supercooling effect.The experiment was performed by using DC voltage and 0.3 mm diameter of copper electrode. The time-dependent temperature is was measured using thermocouple data logger which is connected to a computer. The parameter variation consist of the magnitude of applied electric field and interval time for field application. It turns out that the minimum amplitude of applied field is about 700 V, and the supercooling degree tend to decrease with the increase of applied field. The supercooling degree also changed with the interval time for the applied field, although its variation still need to be further clarified. From this experiment, it can be concluded that DC voltage affects the supercooling degree of CaCl2.6H2O and help to create the nucleation process.

Keywords
Electrofreezing, Solidification, Salt Hydrate CaCl2.6H2O, Supercooling

Topic
Functional Materials

Link: https://ifory.id/abstract/2a3QKuFYzHc4

Corresponding Author
Edy Wibowo

Institutions
1Engineering Physics, School of Electrical Engineering, Telkom University, Jalan Telekomunikasi No.1, Terusan Buah Batu, Bandung, Indonesia.
2Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang (UNNES), Gunungpati, Semarang, Indonesia.
3Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Jember, East Java, Indonesia.

Abstract
We report the attempt of utilization rice husk-IR 64 as green adsorbents for degrade methylene blue in aqueous solutions. We attempted to significantly enhance the degradation ability of rice husk, but through a simple process i.e. drying in the sun and boiling in the aquadest. The percent degradation of MB in the solutions was determined by using photometer apparatus, while the change of transparence of the solution after treated by activated rice husk was measured by UV-vis spectrometer. We obtained that the boiling treatment is more effective for enhancing the degradation ability of rice husk than sunbathing process. The use of boiled rice husks could reduce MB in the solutions up to 89%. Indeed, the degradation ability of rice husk-IR 64 can be significantly increase through simple treatment so that it possess a great chance to develop as green adsorbent with marvelous performance.

Keywords
rice husk, IR 64, degradation, methylene blue, aqueous solutions

Topic
Functional Materials

Link: https://ifory.id/abstract/y9UNwknagP3J

Corresponding Author
Mamat Rokhmat

Institutions
a) Universitas Telkom, Jl Telekomunikasi No. 1 Bandung
b) Universitas Jember,
c) Institut Teknologi Bandung, Jl Ganesha 10 Bandung

Abstract
We report the performance improvement Titanium Dioxide based solar cell, according to impedance measurements of the cells. The treatment of solar cells with NaOH has succeeded in increasing the performance of solar cells. The efficiency of solar cells increased to 1.34% and FF by 0.35 after NaOH was carried out after treatment. This increase occurs because of an increase in Na + ions, increased ionic conductivity of electrolytes. In addition, compilation of NaOH after treatment is carried out on a wide surface determined on the aluminum electrode. Increasing, this will increase contact between aluminum and electrolytes. The use of NaOH after treatment and deposition of Cu in TiO2 layers of solar cells was also able to reduce the resistance in solar cells from 4240 ohms before NaOH after treatment to 1550 ohms after NaOH after treatment. As a result, the performance of solar cells is increasing. These results indicate post-treatment NaOH can improve the performance of solar cells

Keywords
Sel Surya, TiO2, Metal deposition, impedance

Topic
Functional Materials

Link: https://ifory.id/abstract/BNJM729fZGkj

Corresponding Author
Dixon Thomas

Institutions
Institut Teknologi Bandung

Abstract
Controlling building thermal environment is an important problem nowdays with many growing cities around the world. More growing cities means more buildings that make the temperature of the environment rise. The thermophysical behavior of this phenomena depends on wall’s thermal properties of wall such as: thermal conductivity, thermal mass, and solar absorbance. This paper presents the results of studies on a wall’s thermophysical behavior with variation of wall’s thermal properties. Simulation carried out by detecting temperature distribution data of wall using Energy2D simulation program of 11 cm thick wall with the area of 1m x 1m, where the wall was exposed to a heat source for 4 hours then the heat source will be turned off for 4 hours. Thermal conductivity, thermal mass, and solar absorptance of wall was varied based on brick wall as the reference wall. The measurement results show that absorbance of the wall determine the amount of heat distributed around the wall, while thermal conductivity and thermal mass of wall determine heat distribution. We conclude that controlling wall’s thermal properties will give specific impact on building thermal environment.

Keywords
controlling thermal environment, thermal properties of wall, wall material

Topic
Functional Materials

Link: https://ifory.id/abstract/tLhWYpNKFVza

Corresponding Author
Febe Merita

Institutions
Center for Science and Nuclear Applied Technology, National Nuclear Energy Agency, Bandung, 40132, Indonesia

Abstract
Recently, nanofluids have attracted much attention due to their properties such as for heat transfer fluids. As heat transfer fluid medium, nanofluid is used for many applications such as heating and cooling processes, power generation and automotive. In the nuclear industry, applying nanofluid as coolant and emergency core cooling system (ECCSs) is seen as a potential method because the properties of nanofluids enhances the heat transfer coefficient and conductivity characteristics of the original fluid. In the present study, nanofluid alumina-water system (g-Al2O3) and water are used as a quenching medium in simulation of loss of coolant accidents (LOCAs). Zircaloy-4 (Zr-4) fuel cladding was used in this experimental. Zircalloy-4 was annealed in various temperature (1000 to 1250 C) at 1 hour then quenched in alumina-water nanofluid and water. After quenching, the mass gain of Zr-4 fuel cladding was observed as the function of annealing temperature. Optical microscope, XRD and SEM EDS is used to identify the Zr-4 fuel cladding after annealed. Optical microscope characterization shows that alumina-water nanofluid effectifely reduce cracks on surface of the Zr-4 fuel cladding at temperature up to 1200ºC. X-Ray diffraction (XRD) analysis shows that the oxide scale ZrO2 formed on the surface of Zr -4. Characterization by Scanning Electron Microscope (SEM) shows that the thickness of oxide layers increase with increasing annealing temperature. This study demonstrated the effect on nanofluid alumina-water system to reduce oxidation rate of Zr-4 fuel cladding. Lower oxidation rate of Zr-4 fuel cladding in nanofluid alumina-water system has been obtained compared to water.

Keywords
nanofluid, oxidation, zircaloy-4, alumina-water nanofluid, heat transfer, nuclear safety

Topic
Functional Materials

Link: https://ifory.id/abstract/pt2DMV79ArB3

Corresponding Author
Yohanes Edi Gunanto

Institutions
1Dept. of Physics Education, University of Pelita Harapan Karawaci, Tangerang 15811, Indonesia
2Center for Science and Technology of Advanced Materials, BATAN, Tangerang Selatan 15314, Indonesia

Abstract
The efforts to increase reflection loss through material engineering on magnetic materials based on barium strontium hexaferrites have been carried out. The engineering of this material was in the form of lanthanum substitution in the Ba0.6Sr0.4-xLaxFe10MnTiO19 system (x = 0.05, 0.1, and 0.15) which was synthesized by the solid reaction method through mechanical milling technique. Crystal structure, morphology, complex permittivity, and successive complex permeability have been measured using X-ray Difraction (XRD), Scanning Electron Microscopy (SEM) and Vector Network Analyzer (VNA). Based on the results of qualitative analysis, it is showed that the formation of single phase ultrafine particles was successfully confirmed. Quantitative analysis of XRD data showed that there were changes in structural parameters along with changes in the value of x. The observation studies with SEM showed that the synthesized particles had hexagonal morphology. Reflection loss (RL) are -20.1 dB, -24.7 dB, and -20.3 dB for x = 0.05, 0.10 and 0.15, respectively. It was concluded that this material can be applied as a microwave absorber (RADAR).

Keywords
reflection loss; microwaves; milling; Ba0.6Sr0.4-xLaxFe10MnTiO19

Topic
Functional Materials

Link: https://ifory.id/abstract/b6zXR73mcDMg

Corresponding Author
Sutikno Madnasri

Institutions
Physics Department, Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang
Sekaran Gunung Pati Kota Semarang Jawa Tengah, Indonesia, 50229
*Email: smadnasri[at]yahoo.com

Abstract
The main problem in the fabrication of dye-sensitized solar cell (DSSC) is the achieved efficiencies have been still relatively low namely under 5%. This make the fabricated devices have not been unable to compete and replace the conventional solar cell role. In this research, the microwave irradiation is applied in coating anthocyanin of musa acuminata bract to improve absorbed anthocyanin dyes in the work electrode so that the absorbed light intensities increased as well. The Electrolux Microwave (EMM 2308X) pada daya 140 Watt was used to generate microwave irradiation and expose it on the thin film surface. The DSSC electrical properties were determined using I-V meter El-Kahfi 10.

Keywords
DSSC; Irradiation; Microwave; Musa Amicunata bract

Topic
Functional Materials

Link: https://ifory.id/abstract/BPmErhRY9w4X

Corresponding Author
Septia Refly

Institutions
(a) Department of Physics, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia
(b) Department of Chemistry, Universitas Pertamina, Jl. Teuku Nyak Arief, Simprug, Jakarta 12220, Indonesia
(c) National Center for Sustainable Transportation Technology, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia
(d) Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, Indonesia
*ferry[at]fi.itb.ac.id

Abstract
Dealing with the high price of lithium-ion batteries (LIBs) constituent materials, researchers around the world are seeking for the new source to assure sustainability of battery production. Valuable metals from spent LIBs can be used as a secondary source for LIB cathode production, which can be recovered through metal extraction in the form of acid leaching process of the cathode material. This action is not only economically beneficial but also able to reduce environmental and health hazards due to heavy metals contained in LIBs waste. In this study, citric acid was used as a leaching agent to extract Li, Co, Ni, and Mn metals from the active material cathode LiNi1/3Co1/3Mn1/3O2 (NCM 111). The addition of sucrose as a reducing agent was able to increase leaching efficiency, indicated by the increase of metal ion concentration in the filtrate. Based on this study, optimal conditions of the leaching process are the citric acid concentration of 1.2 M, reaction temperature of 80 ⁰C, reductant dosage of 0.5 g/g, the reaction time of 90 minutes, stirring speed of 400 rpm and solid to liquid ratio of 20 g/L. Transition metal ions in the filtrate are then co-precipitated to obtain salt precipitate through oxalate co-precipitation process. The dried precipitate had a crystalline structure of MC2O4⋅2H2O (M = Co, Mn, Ni), as was confirmed by XRD analysis. Organic acids leaching and oxalate co-precipitation process were able to recover valuable metals from spent LIBs through an environmentally friendly procedure.

Keywords
Lithium ion batteries (LIBs), NCM 111, Recycle, Citric acids, Oxalate co-precipitation

Topic
Functional Materials

Link: https://ifory.id/abstract/zVJ9Q4PARCDF

Corresponding Author
Ayi Bahtiar

Institutions
Department of Physics Universitas Padjadjaran
Jl. Raya Bandung-Sumedang Km. 21 Jatinangor Sumedang Jawa Barat 45363

Abstract
Hybrid organic-inorganic perovskite solar cells have great attention as good alternative for replacing conventional silicon solar cells due to their high-performance and low-cost processing. Nowadays, the power conversion efficiency (PCE) of perovskite solar cells has reached more than 22% which is comparable with commercially available silicon solar cells. However, their low-stability in high humidity hinders the commercialization of perovskite solar cells. Therefore, the research of perovskite solar cells is now shifted to stability study rather than achieving high performance. We have prepared perovskite from mixed methylammonium iodide (MAI) and lead (II) iodide or PbI2 as active layer of solar cells with structure hole-transport-layer (HTL) free consisted of Glass/FTI/TiO2/ZrO2/perovskite/carbon. Due to its instability of MAI on humidity, we have doped MAI with Cesium to improve both performance and stability of perovskite solar cells. We have varied the concentration of cesium ranging from 5% to 20%. The stability study was conducted at room temperature (25C) and room relative humidity (80-85%). We have used white LED with intensity 100 mW/cm2 as light source in current-voltage measurement of solar cells. We have found that the highest PCE and stability of perovskite solar cells was achieved by doping 10% of Cesium.

Keywords
perovskite solar cells, HTL-free, cesium, performance, humidity

Topic
Functional Materials

Link: https://ifory.id/abstract/rGKbzR2nCPmZ

Corresponding Author
Kormil Saputra

Institutions
a)Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang No. 5, Malang 65145, Indonesia
b)Research Center of Minerals and Advanced Materials, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang No. 5 Malang 65145, Indonesia
*Corresponding Author’s Email: sunaryono.fmipa[at]um.ac.id

Abstract
Availability Natural Iron Sand that abundant in Indonesia as the main source of ingredient magnetic is a potential raw material for synthesizing of Mn0.25Fe2.75O4/AC. Preparation of Mn0.25Fe2.75O4 /activated carbon (AC) has been successfully synthesized by using the co-precipitation method. Furthermore, the variations of AC mass in Mn0.25Fe2.75O4/AC filler composition also has been done to find out the effect of nanostructural and magnetic Properties from the contribution of Mn0.25Fe2.75O4/AC that characterizes by using X-Ray Diffraction (XRD) and Vibrating Sample Magnetometer (VSM) instrument respectively. The particles size of Mn0.25Fe2.75O4/AC with the filler of AC 0.1, 0.2, and 0,3 g by using XRD characterization is 7.4, 3.67 and 11.8 nm recpectively. Based on VSM Characterization, the value of Magnetization saturation of Mn0.25Fe2.75O4/AC is 0.77, 0.003, and 0,002 emu.gram-1 with the filler of AC 0.1, 0.2, and 0.3 g respectively.

Keywords
nanostructural, Mn0.25Fe2.75O4, AC, and Magnetic Properties

Topic
Functional Materials

Link: https://ifory.id/abstract/tP23ck4JGLpw

Corresponding Author
Bhre Wangsa Lenggana

Institutions
a) Faculty of Engineering, Universitas Sebelas Maret
Jl. Ir. Sutami 36A, Surakarta 57126, Indonesia
*ubaidillah_ft[at]staff.uns.ac.id
b) Faculty of Engineering, Universitas Andalas
Jl. Universitas Andalas, Kota Padang 25163, Indonesia

Abstract
This case study proposes the development of damping technology using intelligent materials as working fluids for landing gear of unmanned aerial vehicles (UAV) during the landing process. The intelligent materials to be used is magnetorheological fluids (MRF), a liquid that has variable viscosity to magnetic fields. This intelligent material can improve the performance of the damping device by allowing it to have variable damping feature through viscosity changing. The proposed UAV magnetorheological (MR) dampers design utilizes a magnetic valve that has an annular flow channel configuration with 0.5 mm gap size equipped with electromagnetic coil with adjustable current input. Both gap size and the current input selection affect the performance of the damping device. This study discusses the performance to reduce shock during landing process. The performance is evaluated by analyzing the pressure drop and damping force produced by the device with changes in the current input variation. The numerical and simulation results show that the damping characteristics of the device could be adjusted by changing the current input to the electromagnet. The obtained results are then adjusted based on the needs of the UAV in landing purpose. The study proved that the device performance is suitable to absorb shock during the landing process of the UAV.

Keywords
UAV, MR damper, MRF, vibration, damping device, landing process

Topic
Functional Materials

Link: https://ifory.id/abstract/tN839BJGn2YM

Corresponding Author
Hilma Eka Masitoh

Institutions
1)Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
2)Department of Physics, Faculty of Science and Technology, Universitas Islam Negeri Sunan Gunung Djati, Jl. A.H. Nasution 105, Bandung 40614, Indonesia

Abstract
Organic-inorganic CH3NH3PbBr3 perovskite nanoparticle have emerged as highly promising semiconductor materials for photovoltaic and optoelectronic applications such as solar cells, light emitting diodes (LEDs), and other luminescent devices because of their optical properties and electrical conductivity. The optical properties of perovskite can be manipulated when bulk structures change into lower-dimensional structures to obtain the desired optical properties. However, perovskite suffers from a stability problem that makes it degrade easily. Fumed silica (SiO2) is one of the complementary material that is expected to improve the photoluminescence stability of perovskite. In this study, we added fumed silica (SiO2) as a composite material to CH3NH3PbBr3 perovskite nanoparticle, with a varied precipitation temperature prepared by ligand-assisted reprecipitation method (LARP). A preliminary study of the SiO2 effects was conducted based on the photoluminescence (PL) characterization using a fluorescence spectrophotometer, UV-Vis spectroscopy, and transmission electron microscopy (TEM).

Keywords
Perovskite, photoluminescence, stability, fumed silica (SiO2).

Topic
Functional Materials

Link: https://ifory.id/abstract/rAQ6WMnCL2Dh

Corresponding Author
Hartatiek Hartatiek

Institutions
Department of Physics, Faculty of Mathematics and Science, Universitas Negeri Malang 65145 Malang, Indonesia

Abstract
The excellent properties of hydroxyapatite (Ca10(PO4)6(OH)2) have attracted the interest of researchers and engineers for various applications. Instead of using expensive commercial raw materials, we introduced the use of natural minerals for hydroxyapatite synthesis, precisely the calcite rock from Jember, Indonesia. Our study confirmed that the calcium content in the calcite rock was 98.36%. As a bone substitution compound, hydroxyapatite needs to be composited with polymeric materials, such as polyethylene glycol to improve its mechanical properties. The XRD test results showed that variations in the composition of polyethylene glycol affect diffraction peak intensities, lattice parameters, and grain size of crystalline hydroxyapatite-polyethylene glycol nanocomposites. The density value of the nanocomposites increases with the addition of polyethylene glycol up to 4.29 g/cm3. In addition, the value of hardness also increases with the addition of polyethylene glycol up to 78.50 HVN.

Keywords
hydroxyapatite, polyethylene glycol, nanocomposite, density, hardness

Topic
Functional Materials

Link: https://ifory.id/abstract/RKAa7Xnemyfp

Corresponding Author
Sahrul Saehana

Institutions
a)Physics Education Departement, FKIP Tadulako University, Indonesia
* sahrulsaehana[at]gmail.com
b) Agribussiness Departement, Agriculture Faculty, Tadulako University, Indonesia

Abstract
This study reports characterization of polymer from Lanea coromandelica (houtt) merr which fabricated using solution casting methods. Investigation by scanning electron microscopy (SEM), Electron Dispersive X-Ray (EDX), FTIR, and impedance spectroscopy were done. We found that natural polymer based membrane polymer electrolyte contained metal ion such us silikon and aluminium. It was also found that electric conductivity was about 2 x 10-2 S/m3. We predicted that metal ion contained make the polymer electrolyte be conductive. It was predicted that its polymer was potential for electronic device application. On the other hand, the natural polymer also potential to change plastic application.

Keywords
natural polymer, membrane polymer, application

Topic
Functional Materials

Link: https://ifory.id/abstract/U7uZjGPqYWBd

Corresponding Author
Fathinnatussifa Uliyahanun Zuhri

Institutions
a)Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, 65145 Malang, Indonesia
*markus.diantoro.fmipa[at]um.ac.id
b)Centre of Advanced Materials for Renewable Energy, Universitas Negeri Malang, 65145 Malang, Indonesia
c)Institute of Science, School of Physics, Suranaree University of Technology 111 University Ave., T. Suranaree Muang District, Nakhon Ratchasima, Thailand

Abstract
Ni-Co MOF-based systems have been proposed as supercapacitor electrode materials because they show high energy capacitance. However, most MOFs have poor electrical conductivity and narrow micropores which limit the diffusion within the pores. To overcome the weakness of this MOF, MOF can be composite with ZnO and Functionalize Carbon (FC) on the system. This study aims to determine the effect of adding Ni-Co MOF in the ZnO-FC-NiCo MOF system on aluminum substrates to the performance of the supercapacitors produced. The Ni-Co MOF was successfully prepared by the reflux method at 140 °C. ZnO and FC materials are mixed with the addition of Ni-Co MOF mass of 10% and 20% of the total mass, with the blending method for 5 hours. Supercapacitors were arranged symmetrically using 0.5M H3PO4 electrolytes. The samples characterization were carried out using XRD, SEM-EDX, Cyclic Voltammetry, and EIS. It is shown that specific capacitance is increasing, ranged from 1.15 to 6.62 F/g.

Keywords
Supercapacitor, Ni-Co MOF, ZnO, FC

Topic
Functional Materials

Link: https://ifory.id/abstract/ahUpjkwP4qcE

Corresponding Author
Mira Setiana

Institutions
1) Department of Physics, Faculty of Mathematical and Science, Universitas Brawijaya, Jl. Veteran, 65145 Malang, Jawa Timur
a)mirasetiana[at]student.ub.ac.id
b)tyasnz[at]student.ub.ac.id
c) sakti[at]ub.ac.id

Abstract
Quartz crystal microbalance respond not only to the deposited mass on its surface, liquid property in contact with its surface, but also respond to the mechanical property change of its coating material. The mechanical property of the coating material which affects the sensor resonance frequency is the modulus elasticity change, mass density change and conformational change of the coating layer. It is known that the polymer mechanical property can be affected by the gas or liquid in contact with the polymer. Gas or liquid absorption leads to the change in the modulus elasticity of the film which absorb the gas or liquid compare to the initial film modulus elasticity. Ionic interaction may also affect the polymer film mechanical property. Potassium chloride solution in water has ionic strength related to its concentration. This work shows that the frequency respond of the QCM sensor coated with polystyrene was affected by the potassium concentration in water. The frequency change of the QCM sensor coated with polystyrene film to the potassium chloride concentration from was presented.

Keywords
Quartz crystal microbalance; Potassium chloride; Polystyrene

Topic
Functional Materials

Link: https://ifory.id/abstract/ebXDPmChQFqL

Corresponding Author
Robi Kurniawan

Institutions
1 Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, East Java, Indonesia
2 Centre of Advanced Materials for Renewable Energy, Universitas Negeri Malang, Jl. Semarang 5, Malang, 65145 East Java, Indonesia

Abstract
Alumina based catalysts play an important role in the process of optimizing crude oil processing. Platinum/alumina (Pt/Al2O3) is an alumina based catalyst that is widely used in the oil production process, as a consequence leaving a lot of catalyst waste. In this catalyst waste, the Pt metal is an important content, which has a high economic value. In this study, we focused on processing Pt/Al2O3 catalyst waste to separate Pt metal content from the catalyst. Optimization of Pt metal separation was carried out using a sonoleaching procedure under different conditions. We noted a significant change in the color of the catalyst from gray to yellow and a reduction in mass at an increase in temperature of up to 50oC during the sonoleaching process. Furthermore, the effect of temperature on recovery of Pt metal was investigated by morphological analysis and elemental content in Pt/Al2O3 catalyst waste. Our results will provide additional knowledge and reference in optimizing Pt recovery in Pt/Al2O3 catalyst waste for the reuse of Pt metals in various applications.

Keywords
Pt/Al2O3 catalyst; sonoleaching; temperature; Pt metal

Topic
Functional Materials

Link: https://ifory.id/abstract/mj6XPf3BcxTV

Corresponding Author
Is Fatimah

Institutions
Kampus Terpadu UII, Jl. Kaliurang Km 14, Yogyakarta, Indonesia 55584

Abstract
Surface modification onto Salacca skin with sodium dodecyl sulfate (SDS) for enhancement adsorption capability toward methylene blue (MB) and batik’s wastewater has been conducted. Research was focused on the change of physicochemical character of adsorbent using gas sorption analyses and Fourier-Transform Infra-Red (FTIR) spectrophotometric analysis. Performance of modified Salacca skin for MB and batiks wastewater was evaluated in batch adsorption system for kinetics and optimization study. The results showed that surface modification is in favor for enhancement the adsorption of MB and batik’s wastewater. The presence of functional group on surface plays important role for the surface interaction to enhance adsorption capability. The equilibrium data of MB adsorption by batch system reveals that the adsorption kinetics obey pseudo-first order kinetics and the mechanism described the more intensive surface interaction by surfactant modification.

Keywords
Adsorption; Batik’s wastewater; Biosirbent; Dye; Surfactant

Topic
Functional Materials

Link: https://ifory.id/abstract/FEKBwf9ADnGU

Corresponding Author
Rizky Aditya Sawitri

Institutions
a) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang 5 Malang 65145, Indonesia
b) Centre of Advanced Materials for Renewable Energy, Universitas Negeri Malang, Jl. Semarang 5 Malang, 65145, Indonesia
*markus.diantoro.fmipa[at]um.ac.id

Abstract
Thermoelectric materials can convert heat energy into electrical energy. Thermoelectric uses three effects were Seebeck, Peltier, and Thomson effects. Good thermoelectric materials exhibit a large Seebeck coefficient, high electrical conductivity, and low thermal conductivity so that the material might show a good figure of merit (ZT) coefficient. A series of Co4Sb12 skutterudites compound shows excellent potential as a thermoelectric material because Sb-based skutterudites thermoelectric materials possess high mobility, large atomic mass, low electrical resistivity, and Seebeck coefficient reaches up to 200 µV/K. So far the compound was synthesized based on interstitial doping. In this paper, we report on the study preparing of Co4Sb12 skutterudites for which introducing transition metal atom (Ni) ion at Co site to modify a local distortion which in turns to increase of ZT value. Co4Sb12 skutterudites were synthesized using the modified polyol method and fabricated into thin films on glass substrates. Before fabrication, Co4Sb12 skutterudites was dissolved into DMF. The fabricated Co4-xNixSb12 skutterudites films were characterized using XRD, SEM-EDX, UV-VIS, and I-V meter to determine the structure and thermoelectric properties of Co4-xNixSb12 skutterudites. It is found that the crystal system of obtained Co4-xNixSb12 skutterudites falls to cubic with the space group of Im-3 (204). Further analyses of XRD data also shows that the crystallinities are 7.65 and 9.35%, for samples respectively for x = 0 and 0.1. The phase purity of the Co4-xNixSb12 samples reach up to 74, and 63% for x = 0 and 0.1 respectively. The result of UV-VIS spectra analyses shows the band gap for samples x = 0 and 0.1 were 2.59 and 2.66 eV, which indicates the samples are semiconductors like which lower than semiconducting oxides. The I-V meter result shows that the increased electrical conductivity with increasing temperature, indicating that the samples can be used as a raw material for the thermoelectric device. Besides that, the values of electrical conductivity for samples reach 10-4 Ω-1. cm-1, which also indicates the samples were semiconductors.

Keywords
Thermoelectric, Co4Sb12 skutterudites, crystal system, band gap, conductivity

Topic
Functional Materials

Link: https://ifory.id/abstract/MJNHKhUyTkrV

Corresponding Author
Safira Mintari Jayadininggar

Institutions
a)Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang 5 Malang 65145, Indonesia
b)Centre of Advanced Materials for Renewable Energy, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, Indonesia
c)Department of Physics, Universitas Negeri Surabaya, 60254 Surabaya, Indonesia
*markus.diantoro.fmipa[at]um.ac.id

Abstract
Nowadays, solar cell is one of the most promising energy conversion devices. DSSC as a third generation of solar cell extensively developed due to their advantages i.e. simple fabrication route, eco-friendly, and lower costs. The working principle of DSSC system is based on dye photon absorbing agents provided by photoanode which is consist of high band gap semiconductor materials. ZnO has been widely used due to its high level of electron mobility. However, the energy efficiency level of ZnO-based DSSC is lower than TiO2-based DSSC. So far there is no comprehensive study about TiO2@Ag-TiO2 nanocomposite as photoanode of organic DSSC. In this study, TiO2 as an inert material is used to encapsulate silver (Ag) from corrosion. Experimentally, ZnO and Ag@TiO2 nanoparticles were synthesized using coprecipitation and one-pot synthesized method, respectively at various molar ratio. The phase and structure were analyzed using X-ray Diffraction with Cu-Kα radiation. SEM-EDX is utilized to observe the morphology of the sample and identify their elements composition. The optical band gap was calculated via Tauc plot method from UV-Vis spectroscopy data. For confirming the photovoltaic performance of system, solar simulator with Keithley I-V meters was applied.

Keywords
nanocomposite, organic DSSC, TiO2/ZnO-Ag@TiO2, photovoltaic performance

Topic
Functional Materials

Link: https://ifory.id/abstract/aPDcwEh8X9T6

Corresponding Author
Ashianti Stenny Winata

Institutions
(a) Department of Chemical Engineering
Institut Teknologi Bandung, Bandung 40132 Indonesia
(b) Department of Chemical Engineering
Universitas Katolik Parahyangan, Bandung 40141 Indonesia
*santi[at]unpar.ac.id

Abstract
Supercapacitor is considered as promising technology in energy storage system (EES) because of high power, large currents, and excellent cycle stability. In this study, activated carbon was used as the constituent material for electrodes because it owns porous structure with large surface area, owns high conductivity, low cost, and renewable Activated carbon was synthesized from salacca peel by hydrothermal carbonization and chemical activation with KOH. Salacca peel was chosen as a precursor because it has high fixed carbon content and low ash content, but usually discarded as a waste. This research focused on the effect of operating pressure in the hydrothermal carbonization process. The the operating pressure used will determine the water phase in the hydrothermal process, where in this study the pressure is adjusted so that the water is varied in the vapor phase and liquid phase (subcritical water). In hydrothermal carbonization, temperature was varied at 225oC and 250oC with the carbonization time of 5 hours. Chemical activation using KOH as activating agent was done after obtained the hydrochar from hydrothermal carbonization process. Produced activated carbons were characterized by nitrogen adsorption-desorption, scanning electron microscope, Fourier transform infrared, X-ray diffraction, and Raman spectroscopy. Electrochemical properties of these carbons were characterized by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. It is found that the largest surface area of produced activated carbons could be obtained is 2907.31 m2/g and the largest capacitance of supercapacitor is 15.57 F/g.

Keywords
activated carbon; salacca peel; hydrothermal carbonization; subcritical water; supercapacitor

Topic
Functional Materials

Link: https://ifory.id/abstract/9rjhw3CWnERV

Corresponding Author
Sutikno Madnasri

Institutions
Advanced Composite Laboratory, Physics Department, Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang
Sekaran Gunung Pati Kota Semarang Jawa Tengah, Indonesia, 50229
*Email: smadnasri[at]yahoo.com

Abstract
The purpose of this research is to characterize Hibiscus tiliaceus L. flowers for green photoresist application. As an organic material, it is expected become an alternative to substitute chemicals have been used to date in it’s synthesis process. This research was designed in four steps, namely flower extraction, characterization of thin films of extracted flower liquid, photoresist fabrication, and characterization of photoresist thin films. The liquid mass fraction of Hibiscus tiliaceus L. flowers was optimized in the range of 10-50% using distillation method. The ocean optic Vis-NIR USB 4000 and Perkin Elmer Frontier FT-IR were used to investigate their optical properties and while Digital CCD Microscope MS-804 Scopeman was used to observe their microstructures. The electrical properties were studied using I-V Meter Elkahfi 100. The photoresist sensitivities were determined through UV and X-ray exposures on their surfaces and the simple patterns were designed for this work. The manufactured organic photoresist matched on the absorbance in wavelength range of 350-1050 nm with the highest absorbance value of 0,3.

Keywords
Epoxy; Hibiscus tiliaceus L.; Photoresist; Photosensitivity

Topic
Functional Materials

Link: https://ifory.id/abstract/qGDrtTRCxANL

Corresponding Author
Hendri Widiyandari

Institutions
a) Department of Physics, Sebelas Maret University, Surakarta, Indonesia
b) Departement of Chemical Engineering, Sebelas Maret University, Surakarta, Indonesia
c) Departement of Physics, Diponegoro University, Semarang, Indonesia

Abstract
The PVDF/SiO2 (Polyvinilidene fluoride/Silica) nanofiber membrane were prepared by electrospinning method. The SiO2 colloid nanoparticle concentration was varied at 500, 1000 and 3000 ppm. The PVDF is a material that developed in the manufacture of separators. The PVDF has a higher polarity, melting point and electrolyte uptake than the PP material commercial separators. The effect of the SiO2 nanoparticle addition to the PVDF nanofiber membrane to improve membrane characteristics which include porosity, high temperature stability mechanical, mechanical strength and the stability of battery capacity were systematically investigated. The parameter of electrospinning method with 15 kV voltage, flow rate 1,5 ml / hour, needle distance with collector 17 cm and time 1 hour. The immersion of PVDF membrane in colloid SiO2 nanoparticles was carried out for 1 hour. The shape and fiber size were analyzed by SEM (Scanning Electron Microscope). The SEM image shows the PVDF nanofiber membrane which has beaded fibers with an average fiber size is ~ 656 nm. The nanoparticel SiO2 formed double layer on the PVDF membrane. The porosity effect of PVDF without SiO2 and PVDF/SiO2 3000 ppm is 57% and 70%, respectively. The effect of addition SiO2 to mechanical strength were increased until 2.7 MPa and the membrane were stable at 150 C for 30 minutes. The PVDF membrane has a higher specific capacity than the PP membrane that is 104.6 mAh/g. The addition of SiO2 nanoparticles increased the PVDF membrane capacity stability by the decrease of specific capacity of 42.7 mAh/g for PVDF membrane to 18.7 mAh/g with the addition of SiO2 3000 ppm nanoparticles.

Keywords
PVDF/SiO2; Separator; Membrane; Nanofiber; Electrospinning; Li-ion Battery

Topic
Functional Materials

Link: https://ifory.id/abstract/n94CTcXLedrq

Corresponding Author
Pierre Wolter Winowatan

Institutions
a) Department of Metallurgy and Materials, Faculty of Engineering, Universitas Indonesia, Depok, Indonesia
*winowatan.pierre[at]gmail.com
b) Center for Research of Physics, LIPI, Puspiptek Serpong,
Tangerang, Indonesia

Abstract
Titanium dioxide is a promising candidate to be used as anode material for lithium-ion batteries. It has some notable polymorphs such as rutile and anatase, etc. Although several studies revealed that one type of polymorph is better than other polymorphs, comparison between different polymorphs using same synthesis method is still unclear. This research discuss about electrochemical performance between 2 polymorphs of rutile and anatase synthesized by using sol-gel method followed by calcination process. The temperature for calcination process for rutile and anatase polymorps are 480 °C for 8 hours and 850 °C for 6 hours respectively. The synthesis of both rutile and anatase polymorphs has been a success with high purity and no impurity peak shown by XRD result. In this research, a sample of commercial TiO2 is used to make a coin cell battery to compare the performance between other samples. The electrochemical performances are examined by CV, CD and EIS.

Keywords
Rutile; Anatase; Titanium Dioxide; Lithium-ion Battery

Topic
Functional Materials

Link: https://ifory.id/abstract/g4dGDEbYHQze

Corresponding Author
Ahmad Rifqi Muchtar

Institutions
1,3. Electrical Engineering, State Polytechnic of Jakarta, Depok, Indonesia
2. Department of Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Indonesia
4,5. Civil Engineering, State Polytechnic of Jakarta, Depok, Indonesia

Abstract
Metal Oxide Semiconductor (MOS) material is chosen as a gas sensor because of its nature which can be modified as needed. In this research SnO2 is choosen becoause of its chemical and physical stability compared to the other MOS. However for gas sensor application, SnO2 have drawbacks of low selectivity and high operating temperature. To overcome those drawbacks, the SnO2 is mixed with graphene by molar ratio 1:1, and synthesized with polyol method using ethylene glycol as solvent, at 197 oC for 12 hours. The resulting material is then settled, and calcined at 550 oC. The characterization used are SEM, TEM, EDS, UV-Vis spectrophotometers, and gas sensor performance test with CO gas. The particle size are in range of 5-15 nm. The band gap test result of SnO2-graphene is 2,94 eV which decrease 0,62 from SnO2 band gap. The detection of 20 ppm CO gas for 10 minutes result in highest sensivity of 59% at 300 oC.

Keywords
Semiconductor, SnO2, Graphene, Polyol, UV-Vis

Topic
Functional Materials

Link: https://ifory.id/abstract/ZEvNWmnLtARQ

Corresponding Author
Lina Suryanti

Institutions
a)Department of Physics, Faculty of Mathematics, Universitas Negeri Malang, Jl. Semarang 5, Malang, Indonesia
*markus.diantoro.fmipa[at]um.ac.id
b)Centre of Advanced Materials for Renewable Energy, Faculty of Mathematics, Universitas Negeri Malang, Jl. Semarang 5, Malang, Indonesia
c)Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret, Jl. Ir. Sutami 36A Kentingan Jebres Surakarta 57126, Indonesia
d)Department of Physics, Faculty of Science, Universitas of Malaya, 50603 Kuala Lumpur, Malaysia

Abstract
Supercapacitor is one of the energy storage devices with excellent of storing electrical energy, long cycle stability, high energy density, easy construction, environmentally friendly, has the ability to store fast power and longer discharge. Graphene, activated carbon, zinc oxide, and Mn2O3 are good materials which commonly used as supercapacitor electrodes. ZnO-C-based supercapacitor research is currently underway and shows considerable capacitance. Addition of manganese oxide such as Mn2O3 in ZnO-C film will produce good specific capacitance because carbon will reduce the poor conductivity of manganese oxide. This study aims to determine the effect of adding Mn2O3 in the ZnO-C-x(Mn2O3) system to the performance of the supercapacitor produced. Mn2O3 nanoparticles were synthesized using the chemical co-precipitation method. Characterization of ZnO-C-x(Mn2O3) symmetric supercapacitor was carried out using XRD, SEM-EDX and Cyclic voltammetry. The results indicated that as the increase in mass addition of Mn2O3 caused the volume of the ZnO-C-x(Mn2O3) film to increase exponentially. The morphology of the ZnO-C-x(Mn2O3) film was the porous film with the highest porosity of 81.67%. Along with the increasing mass addition of Mn2O3, the specific capacitance of the ZnO-C-x(Mn2O3) film increased exponentially from 1.07 to 3.46 F/g. In addition, along with the increase in mass addition Mn2O3, the energy density of the ZnO-C-x(Mn2O3) film increased exponentially from 0.38 to 1.23 Wh/kg.

Keywords
Supercapacitor, Mn2O3, Carbon, ZnO

Topic
Functional Materials

Link: https://ifory.id/abstract/9YPmhevKFdpb

Corresponding Author
Apriwandi Apriwandi

Institutions
a) Department of Physics, University of Riau, 28293 Simpang Baru, Riau, Indonesia
* erman.taer[at]lecturer.unri.ac.id
b) Departement of Industrial Engineering, State Islamic University of Sultan Syarif Kasim, 28293 Simpang Baru, Riau, Indonesia

Abstract
The effect of physical activation temperature in the preparation process of activated carbon electrode for supercapacitorapplication has been analyzed successfully. The activated carbon made from jengkol shell with a combination of chemical and physical activation. The physical activation temperature variated of 800 ˚C, 850 ˚C, and 900 ˚C. High specific capacitances of activated carbon electrode as high as 220 F g-1 was found in physical activation temperature of 850 C. Additionally, physical properties of activated carbon also evaluated such as density, degree of crystallinity, surface morphology and chemical content. These excellent results show great potential for jengkol shell in developing energy storage devices of supercapacitor application.

Keywords
jengkol shell; activated carbon; supercapacitor

Topic
Functional Materials

Link: https://ifory.id/abstract/XYvZabA6gWVu

Corresponding Author
Aldila Putri

Institutions
a)Department of Physics, University of Riau, 28293 Simpang Baru, Riau, Indonesia
* erman.taer[at]yahoo.com
b)Department of Industrial Engineering, State Islamic University of Sultan Syarif Kasim, 28293 Simpang Baru, Riau, Indonesia

Abstract
Potassium iodide (KI) has been added to aqueous-based electrolyte (sulfuric acid / H2SO4) has succeeded in showing the psuedo-capacitance properties that can increase the specific capacitance of supercapacitor cells. The carbon electrodes for supercapacitor cell made from bamboo stems. As supporting data, surface morphology and crystallinity of carbon electrodes have also been analyzed by using SEM and XRD characterization. Whereas in determining specific capacitance of supercapacitor cells, it was carried out using the cyclic voltammetry (CV) method. The CV test results present the addition of KI 0.05 M in 1M H2SO4 solution has increased the electrode specific capacitance from 159 F g-1 to 200 F g-1.

Keywords
aqueous electrolyte; Potassium iodide; specific capacitance; supercapacitor

Topic
Functional Materials

Link: https://ifory.id/abstract/C7hqxHneYBML

Corresponding Author
norman iskandar

Institutions
1st-4th : Department of Mechanical Engineering, University of Diponegoro
5th :Department of Mechanical Engineering, Semarang State University
6th :Department of Mechanical Engineering
University of Wahid Hasyim

Abstract
Austenite temperature must be achieved in the surface hardening process. In the process of surface hardening by the method of flame hardening, failure is often encountered, for example, such as increasing the value of hardness that is not optimal, and the value of hardness that is less uniform The type of fire used, the distance of fire to the specimen, the speed of fire and the level of thickness of the material are factors that are very influential in the process of flame hardening. The purpose of this study is to measure and observe the profile or rate of the trend of increase and decrease in temperature in the flame hardening process in low carbon steel material.The experiment method that is carried out is by giving the variation of the rate. The measurement process uses several thermocouples mounted on the specimen and connected to a computer for the process of data recording and process monitoring. The conclusion of this study is the greater the value of the thickness of low carbon steel material that is processed by flame hardening, so to reach the temperature of austenitization by the method of flame hardening the speed of fire must be slowed. An improper combination between the distance of fire and specimens and the speed of fire can cause austenite temperature not to be reached. The heat reduction rate takes place more slowly than the rate of increase in heat. the speed of fire and distance of fire to low carbon steel which has varying levels of thickness.

Keywords
Austenitization, flame hardening, low carbon steel, temperature, thickness

Topic
Functional Materials

Link: https://ifory.id/abstract/EjuB8UH4Lge7

Corresponding Author
Cipta Panghegar Supriadi

Institutions
a) Department of Metallurgy and Materials, Faculty of Engineering, Universitas Indonesia, Depok, Indonesia
*cipta.panghegar[at]gmail.com
b) Center for Research of Pysiscs, Lembaga Ilmu Pengetahuan Indonesia, Puspiptek Serpong, Tangerang, Indonesia

Abstract
The emerging Portable Device and Electrical Vehicle require safe, portable, and high-power energy sources which may be supplied by Lithium Ion Battery (LIB). The currently available carbon anode in LIB’s system posseses some safety issue such as volume expansion during lithiation/delithiation and formation of solid electrolyte Interphase (SEI) that can be harmful for battery. Accordingly, anode material Li4Ti5O12 (LTO) shows a promising properties that may overcome safety problems caused by carbon anode. However, the low electronic and ionic conductivity are main bottleneck for its application. This research focuses on synthesizing LTO using nano TiO2 synthesized through Sol-gel method. Moreover, the effect of TiO2 crystalline size will be discussed as well. Crystalline size of TiO2 is adjusted by varying calcination temperature at 300oC; 400oC; and 500oC and heated for 6 hours. The crystallite size shown by X-ray diffraction patterns are 7,71 nm ; 15,16 nm ; 23,99 nm, respectively. Furthermore, The obtained TiO2 powder is sintered. The result shows that relatively pure LTO is successfully synthesized using 15,16 nm TiO2. The coin cell are assembled to analyze Li4Ti5O12 anode electrochemical performances.

Keywords
Lithium Ion Battery, Lithium Titanate, Sol gel

Topic
Functional Materials

Link: https://ifory.id/abstract/vD7qLcpJCwn6