Indonesia Conference Directory

Corresponding Author
Ilham Syahidi

Institutions
1 ) Physics Department, Faculty of Mathematic and Science Sebelas Maret University, Surakarta, Indonesia

Corresponding author : *rsuryana[at]staff.uns.ac.id

Abstract
Porous silicon (PSi) has been fabricated using electrochemical anodization method on n-type Si (111) substrate with methanol as an anodizing solution. The ratio of the anodization solution was 1 : 1 for HF and methanol. Platinum was as a cathode while silicon was as an anode. Duration of Anodization time was maintained constant that is 30 min with a variation of current density i.e. 10 mA, 20 mA, 30 mA, 40 mA, and 50 mA. Then the samples were cleaned by boiled H2SO4 and H2O2 with ratio 3:1 and overflow for 5 min. The optical reflectance of the sample was determined using UV-Vis Spectrophotometer and surface morphology was observed using AFM. The reflectance decreased with increasing the current density. AFM images confirmed that pores size and depth increased with increasing the current density. Due to PSi affect reflectance value, it is concluded that PSi can be applied as an anti-reflective material in solar cell devices.

Keywords
Si (111), n-type, electrochemical anodization, reflectance, AFM

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/nLHgdZJDBE8v

Corresponding Author
Nikodemus Umbu Janga Hauwali

Institutions
Physics for Electronic Material Research Division, Department of Physics
Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology

Abstract
A first principles study with density functional theory method has carried for parallelogram graphene nanoflakes. In this work, we used ABINIT package to calculate the fundamental properties of parallelogram graphene nanoflakes in armchair and zigzag types, due to the increase of the number of atoms. The effect of defect for these characters in each type is also presented. Depend on the calculation results, the bandgap of parallelogram graphene nanoflakes only exists in armchair types with largest bandgap 0.021 eV for 54 atoms, while the zigzag types have no bandgap. Based on these results, it can be said that the properties of parallelogram graphene nanoflakes is semimetal. In addition, the density of states results shows that the magnetic properties of parallelogram graphene nanoflakes is non-magnetic since the symmetrical properties between density of states in spin up and spin down. Based on the results study of defect effect, it was found that the defect only affected the bandgap, but not the magnetic properties.

Keywords
parallelogram graphene nanoflakes, density functional theory, bandgap, density of states

Topic
Theoretical and Analysis in Materials

Link: https://ifory.id/abstract/2aGNcqkL7Bjd

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
Merinda Lestari

Institutions
(1) Department of Physics, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, Indonesia.

Abstract
In the present work, we report a green synthesis of CrFe3O4 nanoparticles using Cucumis sativus peel extract as natural surfactant. The coprecipitation route was explored to produce CrFe2O4 nanoparticles by varying Cucumis sativus composition. The CrFe3O4 nanoparticles were characterized by means of X-ray diffractometer, scanning electron microscopy, and Fourier transform infrared spectroscopy. The results of X-ray diffraction data analysis indicated that the change in the diffraction peak to the higher position was influenced by Cucumis sativus composition. All samples constructed spinel structure in a single phase without any impurity. The scanning electron microscopy images showed that the samples had particles size and morphology in the spherical nanometric size. In general, the particles size and distribution of the particles were contributed by Cucumis sativus peel extract composition as a surfactant. Results of the infra-red data analysis presented that the absorption bands for atomic bonds of O-H at the wavelength of 1379, 1614, and 3479 – 3400 cm-1. C-H bonds appeared in the range of 3000 - 3400 cm-1. Furthermore, Fe-O and Cr-O bonds appeared at the wavelength of 430 – 669 cm-1. Therefore, natural surfactant obtained the from peel extract in this work becomes a new potential candidat to produce magnetic nanoparticles in large scale production.

Keywords
Green synthesis, Fe3O4, Cucumis sativus, natural surfactant, nanoparticle

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/CLw2Hyjk3JdN

Corresponding Author
Asdim Asdim

Institutions
a) Division of Physical Chemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Bengkulu, Jl. W.R Supratman, Kandang Limun 38371 A Bengkulu, Indonesia.
*asdim[at]unib.ac.id
b) Division of Inorganic Chemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Bengkulu, Jl. W.R Supratman, Kandang Limun 38371 A Bengkulu, Indonesia.

Abstract
The green synthesis method of SnO2 nanocrystals have been developed in recent year in view of their potential application as photoelectrode in dye-sensitized solar cells (DSSCs). The effect of the size and morphology of SnO2 nanocrystals on efficiency of DSSCs have been reported. In order to prepare SnO2 nanocrystals with different size and morphology, several synthesis methods have been developed. In this report, the facile green synthesis of SnO2 nanocrystals by hydrothermal method at relatively low temperature using plant extracts in acid and base solution have been carried out. SnO2 nanocrystals as synthesized were characterized by an X-Ray Diffractometer (XRD) and a Scanning Electron Microscope (SEM). The results showed that the all products were phase SnO2 nanocrystals which obviously showed by the XRD pattern. Furthermore, SEM images analysis clearly showed the morphology different of SnO2 nanocrystals synthesized with and without the addition of plant extracts. These results indicated that the properties of SnO2 nanocrystals could be controlled using plant extracts in the solution reaction.

Keywords
SnO2; Nanocrystals; Hydrothermal method

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/Wn6chwaBFxKJ

Corresponding Author
Jeyashelly Andas

Institutions
a Faculty of Applied Sciences, Universiti Teknologi MARA, 02600 Arau, Perlis, Malaysia

Abstract
This study introduces hollow activated carbon from kapok (Ceiba pentandra) which were prepared using KOH (CB1) and K2CO3 (CB2) as the activating agents at 1:1.0 (raw kapok: KOH or K2CO3), impregnation time 15 min and activation temperature of 400°C. The iodine number, quantified by Sodium Thiosulphate volumetric titration and percentage yield of CB1 (1446.30 mg/g, 62.60%) was higher compared to CB2 (1200.23 mg/g, 53.50%) which confirmed the effectiveness of KOH as the activating agent. The raw material and prepared activated carbons were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and CHNS/O Analyzer. Absence of certain functional groups were observed for the activated carbons compared to the raw kapok, resulting from the carbonization and activation processes. CHNS/O Analyzer confirmed the increase in carbon content of CB1 (63.93%) and CB2 (62.86%) compared to the raw kapok (43.54%). Hollow tube were viewed from the SEM analysis for all the samples. CB1 and CB2 were evaluated in the transesterification of waste cooking oil (WCO) using 0.2 wt.% catalyst, methanol to oil molar ratio of 3:1 at 60˚C for only 1 h. The percentage of biodiesel yield increased in a trend as given: without catalyst (35.46%) < CB2 (87.46%) < CB1 (89.57%). High catalysis of CB1 was presumably due to its high surface area and high carbon content compared to CB2. This study was successful as it introduces a facile and cheap conversion of waste kapok into promising catalyst for green synthesis of biodiesel.

Keywords
activated carbon, kapok, waste cooking oil, biodiesel, catalyst

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/PZydkLn6vJpK

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
Fanny Arviani Roseno

Institutions
a) Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia
*sugeng[at]eng.ui.ac.id

b) Department of Metallurgy and Materials Engineering, Faculty of Engineering, Universitas Indonesia, Depok 16424, Indonesia

c) Center for Science and Technology for Advanced Materials, BATAN-Indonesia

Abstract
In this study, fabrication process of Ti6Al4V implant material was developed using powder metallurgy. However, due to the high reactivity of titanium with oxygen at high temperature during sintering, TiO2 layer, which is excellent to corrosion resistance loses its protective properties and allows oxygen to diffuse into the bulk of material. This phenomenon is commonly undesirable because it can be detrimental which decreases the quality of material bonds and mechanical properties that causes brittle material. The Arc Plasma Sintering (APS) method was used to protect the material from the formation of an oxide layer (TiO2) on the Ti6Al4V surface and protects from oxygen diffusion. Sintering process was investigated using a new technology of Arc Plasma Sintering (APS). This sintering technology is carried out using both currents and plasma as a heat source which is capable of performing the sintering process with a very short time in just minutes, and low energy consumption. Sintering was performed on 50 A currents with variations in sintering time for 4 minutes, 8 minutes and 12 minutes. The results of the Arc Plasma Sintering (APS) process were compared to sintering using argon atmosphere at a temperature of 1300oC for 2 hours, 3 hours and 4 hours. The material characterization was performed using SEM-EDS and XRD. The density and hardness testing were measured between two methods of Arc Plasma Sintering (APS) and argon sintering. The results of this study indicate that with the Arc Plasma Sintering (APS) method, the material has better density and hardness with a relative density value of 98.40%, hardness value of 375 HV, and the thickness of the TiO2 surface layer continues to decrease from 16.4 µm to 12 µm without any diffusion of oxygen into the material when compared to argon sintering.

Keywords
Ti6Al4V, High Temperature, Arc Plasma Sintering, Oxidation, TiO2 layer

Topic
Theoretical and Analysis in Materials

Link: https://ifory.id/abstract/Kg47urDQRfhb

Corresponding Author
Rahmawati Munir

Institutions
Institut Teknologi Bandung

Abstract
We have investigated new approach to predict mechanical properties for non-homogeneous materials. The investigation use a copy paper 100 gsm as sampling object using image tracking method and based on bending of cantilever slender beam. The copy paper 100 gsm was shaped on non-homogeneous geometris then placing it with curvature angle variations (00, 450 and 900). We snapshot the copy paper sample using digital camera to track bending coordinates at several points after divided the beam image into 16 segments. Futhermore, we calculated Modulus Young using elasticity equation for non-homogeneous beam. The results presented show that it is possible to obtain a good Modulus Young value due to approach Modulus Young value obtained by direct measurement using tensile strenght device. This method is expected to become a reference for developing Modulus Young estimation for non-homogeneous geometri materials without direct contact.

Keywords
modulus elasticity, copy paper 100 gsm, image tracking, cantilever beam

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/v6eUmyYJKdEH

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
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
3 Singapore Synchrotron Light Source, National University of Singapore, 5 Research Link, Singapore 117603, Singapore

a)Corresponding author: robi.kurniawan.fmipa[at]um.ac.id

Abstract
The problem of ozone depletion lies behind the importance of developing a photodetector device, which is used as a preliminary detection step against the risk of solar radiation. At present, hybrid photodetectors are a major concern because they have detection and operational advantages over conventional photodetectors. In this study, we investigated the optical properties and photoresponse of hybrid ZnO/graphene (HZG) systems, of which ZnO nanorod (ZnO NR) was used in the system. Investigations were carried out using spectroscopic ellipsometry (SE) and solar simulators. The results of SE fittings with the effective medium approximation (EMA) method confirmed that the length of ZnO NR was 27.81 nm, 42.67 nm, and 220.46 nm respectively. We note that increasing the size of ZnO NR promotes light absorption to increase significantly. Furthermore, the relationship between light absorption and HZG photoresponse was discussed using comprehensive analysis.

Keywords
Hybrid ZnO/graphene; photodetector; optical absorption; photoresponse

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/DZvpyzNT36xX

Corresponding Author
Muhammad Anshory

Institutions
(a) Departement of Physics, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta 55281, Indonesia
*adib[at]ugm.ac.id
(b) Research Center for Physics, Indonesian Institute of Sciences (LIPI), Tangerang Selatan 15314, Indonesia

Abstract
Recently, two-dimensional (2D) materials have been studied due to its unique properties and potentials for electronic devices. Tin Selenide (SnSe) is a promising material to be developed in many fields by identifying its electronic structure. In this study, we investigate the effect of layer-dependent electronic properties of SnSe using first-principles calculations based on density functional theory (DFT). We firstly optimized layer dependent of the lattice constant and atomic distortion and then calculate the electronic structure-related parameter including band structure and density of electron (DOS). We find that the calculated band gap decreases with increasing the layers of SnSe which is not dependent on fully relativistic calculation by turning spin orbit coupling (SOC). However, we identify substantial spin splitting in the band structure under the presence of the SOC, making this multilayer is promising for spintronics.

Keywords
SnSe; spin splitting; layer-dependent; density-functional theory

Topic
Theoretical and Analysis in Materials

Link: https://ifory.id/abstract/bVyRtn9HN8CE

Corresponding Author
Maya Andansari

Institutions
1Departement of Physics, Faculty of Sciences
Institute of Technology Sepuluh Nopember, Surabaya 60111 Indonesia
*suasm[at]its.ac.id

Abstract
In this study, the composition of (1-x-y)BaTiO3-xBiFeO3-yKVO3 (x = 0.15 ; y = 0.01 and 0.025) were successfully synthesized using a calcination at 700°C for 2 hours of mixed BaTiO3, KVO3 and BiFeO3. Previously, BaTiO3 (BT), KVO3 (KV), and BiFeO3 (BFO) powders were each synthesized through oxalate coprecipitation, solid state reaction, and sol-gel self-combustion method respectively. Phase identification was carried out through X-ray diffraction match software, and further refinement analysis using Rietica software. SEM/EDX analysis was completed for the microstructure characterization, while the impedance complex analysis are used to determine its electrical properties. XRD pattern clarify the absence of the secondary phase in both compositions after calcination, however after sintering the secondary phase Ba3V2O8 was detected. Furthermore, the substitution of 1 mol% and 2.5 mol% doped KV successfully reduce the sintering temperature become ≈1050°C from generally reported 1300⁰C-1400⁰C [1].

Keywords
Barium Titanat, Dielectric, Low Temperature Sintering

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/W4zxcY23eQvw

Corresponding Author
Dui Yanto Rahman

Institutions
Institut Teknologi Bandung

Abstract
Inexpensive solar cell comprising PVA.NaCl polymer electrolyte as hole transport medium and TiO2/graphite composite as photon absorbing materials has been succesfully fabricated. A suspension of TiO2 and graphite was easily deposited on Fluorine Tin Oxide using droplet method followed by heating at 200oC for two hours. PVA.NaCl was used replacing PVA.LiOH as hole trasnport medium. The content of NaCl was varied from 2,4,6,8 and 10 % compared to the content of PVA to achieve the best efficiency. 0.5% efficiency was gained using 6% of NaCl content. Although the efficiency was low, but this type of solar cell is promising to be developed in the future since cheap materials and easy fabrication were used.

Keywords
Titanium dioxide, graphite, efficiency, polymer electrolyte, hole.

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/MuK9hcaDxrUA

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
Yofentina Iriani

Institutions
a) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret. Jl Ir. Sutami 36A, Kentingan, Surakarta 57126

b) Department of Physics, Postgraduate, Universitas Sebelas Maret. Jl Ir. Sutami 36A, Kentingan, Surakarta 57126

Abstract
The effect of Lanthanum (La3+) addition on microstructure, optical and electrical properties of Barium Titanate (BaTiO3) were prepared by using Chemical Solution Deposition (CSD) method. The addition of mole La3+ were 10% and 15% on 0,5 M solubility. Spin coater was used in deposition process of thin films with speed 4000 rpm for 30 seconds. The sandwich-structured Ba1-xLaxTiO3 thin films were grown on a quartz substrate. Thin films were annealed at 850oC with holding time of 1,5 hours. X-Ray Diffraction (XRD) analysis showed the formation of perovskite crystal (ICDD data base PDF

Keywords
CSD, lanthanum, BaTiO3, bandgap energy

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/9LAMBG4Zkcxn

Corresponding Author
Kuwat Triyana

Institutions

Abstract

Keywords
1. Department of Physics, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
2. Department of Chemistry, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
3. Institute of Halal Industry and System, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia

Topic
alpha-pinene, chitosan, molecularly imprinted polymer, selectivity, quartz crystal microbalance

Link: https://ifory.id/abstract/w7d6JnX8fM4R

Corresponding Author
Hartatiek Hartatiek

Institutions
Department of Physics
Universitas Negeri Malang

Abstract
Polyvinyl alcohol (PVA)/Hydroxyapatite (HAp) composite nanofiber was obtained by electrospinning technique using a PVA polymer solution. Variations in the composition of PVA /HAp composite are (100: 0, 90:10, 85:15, 80:20, 75:25, 70: 30 %v). The PVA/HAp composite nanofiber was analyzed including nanostructure, porosity and tensile strength. The characterization of nanostructures using scanning electron microscopy (SEM) showed that the average diameter in the range of 173-234 nm, porosity in the range of 68-77%. The tensile strength test showed that the strain was in the range of 106.9 - 125.5% and tensile strength in the range of 9.77 - 15.85 MPa. This characteristic of PVA/HAp composite nanofiber can be applied as a scaffold in bone tissue engineering.

Keywords
nanostructure, porosity, tensile strength, polyvinyl alcohol, hydroxyapatite, nanofiber

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/djqvFD8u4baP

Corresponding Author
Momang Yusuf

Institutions
(a)PECVD Laboratory, Physics of Electronics Materials Research Group, Physics Department, Bandung Institute of Technology, Jl. Ganesa 10, Bandung, 40132, West Java, Indonesia
*toto[at]fi.itb.ac.id

(b)Physics of Materials Laboratory
Physics Department, Mathematics and Natural Science Faculty, State University of Makassar
Jl. Mallengkeri Raya, Makassar, Indonesia

Abstract
Nickel thin film, aimed at catalyst layer for HWC-in plasma-PECVD-growth of graphene, has been deposited on SiO2 glass by thermal evaporation method. The thickness of the as-deposited Ni films was not uniform ranging from 200 nm to 700 nm as revealed from cross sectional SEM image. To reduce the film thickness and improve the crystal quality of the films, the samples were annealed in the furnace with three different temperatures, T = 400 oC, 500 oC, and 600 oC, for three hours. SEM images of the post-treatment indicated that the film thickness decreased to about 100 – 200 nm after annealed at 500oC for 3 hours. Increasing the annealing temperature to 600oC leads the nickel atoms out of the substrate so that it leaves the substrate without nickel thin film anymore. The disappearing of the Nickel film after annealing at temperature 600oC was confirmed by EDS spectrum examination which showed that there was no nickel element in the sample. Due to the loss of nickel thin film after annealing at 600oC, we set the annealing temperature at 500oC and optimized duration of annealing. It was found that after annealing for 5 hours the thickness of thin film is about 55 nm - 85 nm with some spreaded piles on the film. The obtained thickness of thin film in tens of order magnitude is the expected result for graphene growth.

Keywords
catalyst, graphene, nickel, thin film, HWC-in plasma-PECVD

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/MqxUnGtT9fmh

Corresponding Author
Upik Nurbaiti

Institutions
a) Physics Department, Universitas Negri Semarang, Jl. Raya Sekaran Gunungpati, Semarang 50221, Indonesia
*upik_nurbaiti[at]mail.unnes.ac.id
b) Physics Department, Institut Teknologi Sepuluh Nopember Surabaya, Jl. Arief Rahman Hakim, Surabaya 60111, Indonesia

Abstract
Nano forsterite powders have been successfully synthesized via ultrasonic assistant for the starting materials and followed by solid reaction and calcination steps. The synthesis products were greenish powders with forsterite as the dominating phase as revealed by XRD data analysis. The formation of forsterite was also confirmed by FTIR spectrometry and supported by SEM images. The phase composition after calcination at 950 °C for 4h was 93.9wt% forsterite and 6.1wt% periclase. The forsterite crystal was nanometric according to the XRD data, while the density of the powder was 2.88g/cm3. UV-Vis spectrum of the powder showed relatively strong absorption peaks particularly at 635, 660, 670, 680, 695 and 705 nm which can be associated with the greenish color of the product and is different from previous studies. Therefore, it can be concluded that high purity greenish forsterite can be formed at 950 °C calcination temperature as previously reported, except that the raw materials were subjected to ultrasonic treatment.

Keywords
nano-forsterite; optical characteristics; silica sand; ultrasonic treatment

Topic
Synthesis and Characterization Techniques

Link: https://ifory.id/abstract/Fajm8tVCQHbE

Corresponding Author
Erna Hastuti

Institutions
(1)Department of Physics, Universitas Islam Negeri Maulana Malik Ibrahim Malang
Jl. Gajayana 50 Malang, 65144, Indonesia
*erna[at]fis.uin-malang.ac.id

(2)Research Center for Physics, Indonesian Institute for Sciences (LIPI)
Komplek Puspitek Tangerang Selatan, Banten, 15314, Indonesia

Abstract
In this research, a carbonized chicken feather for anode materials was prepared using the pyrolysis method. While the activation process of carbon utilized KOH variations (1M, 3M, and 5M) which was pyrolyzed at 700 oC. In addition, the surface area, crystalline structures, and morphologies of the activated carbonized chicken feather (CFCAs) were investigated by the X-ray diffraction, BET, FTIR, and SEM. Furthermore, their various electrochemical properties in LIBs were also examined, with the chemical activation process decreasing the crystallite size. The activated carbon has a small reduction and oxidation peaks, which attributed to the insertion of Li-ion into the voids in carbon. The results show that activated carbon with KOH 5 M has the highest discharge rate capacity at 445.87 (mAhg-1).

Keywords
activated carbon, chicken feather, chemical activation, batteries, anode battery

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/KeDc7vLCdkVQ

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
Efendi Mabruri

Institutions
Research Center for Metallurgy and Materials, Indonesian Institute of Sciences

Abstract
The high alloyed austenitic stainless steels such as Fe-15Cr-25Ni type alloys are used in severe environment where a good combination of corrosion resistance and mechanical properties is required in a wide range of elevated temperatures. The high temperature stability of austenitic stainless steels correlates with microstructure of the steels consisted of (-matrix with stable second phases. The alloying elements incorporated into the alloys modify the second phase precipitation and affect the properties. Recently, it is found that the addition of W and Nb into the Fe-15Cr-25Ni steel improved the mechanical propertires and corrosion resistance of the alloys. In this work subsequence investigation has been conducted to clarify the effect of heat treatment on the pitting resistance of the developed Fe-15Cr-25Ni-2W-2Nb steel. The steels were prepared by induction melting following with hot forging and heat treatment. Both the temperature of solution treatment and of aging were varied and the cyclic polarisation were measured on each samples of difference heat treatment temperature. The observation by SEM was taken on some samples for microstructural confirmation. In general, the solution treated sampel had higher pitting potential than the aged ones. The pitting potential increased with the increasing solution treatment temperature. The SEM images showed the precipitation high Nb containing precipitates.

Keywords
pitting resistance, high alloyed austenitic stainless steel, heat treatmen, solution treatment, aging

Topic
Minerals and Complex Materials

Link: https://ifory.id/abstract/7tAHbxhrMcje

Corresponding Author
Rusman Kosasih

Institutions
Material and Metallurgical Engineering Department, School of Post Graduate Studies, Engineering Faculty, University of Indonesia
Kampus UI Depok, Jawa Barat 16424

Abstract
PVD-PLD process nowadays is used to produce a high quality thin film for superconductor – electric layers – medical application – magnetic layers – and resistant coating. This study is a series of PVD research which is used to find the best solution of coating PVD, so that the damage of the tool steel pin made from SKD 61 - hardness 48 ± 1 HRc can be minimized. The research stage was carried out by making research samples in the form of dummy blocks, which are made from SKD 61, PVD-PLD process with 3 types of coating material (AlCr 50:50 – AlTi1 50:50 – AlTi2 63:37), without Active gas such as N or C. The deposition of thin layer showed a promising result condition in which the element of the target exists by testing the samples using FESEM, SEM, XRF, EDS and Micro Hardness Vickers. The characterization testing was done at Physics Research Centre LIPI and PT XYZ Laboratory. The PLD – NdYAG process, which was done using Wave length 1064 nm, Q – switch delay 180 µs/ 70 mJoule - Vacuum 1.16 ~1.35 Torr - Process time 10 minutes, came out with a surface morphology of Al – Ti – Cr particle with 10 – 20 nm amorphous particles. The hardness of surfaces are 474 mHv – 523 mHv (single layer) and 477 mHv – 501 mHv (multiple layer). All of these materials have the same order of hardness from minimum to maximum for both single layer and multiple layer, which is AlCr – AlTi2 – AlTi1. This result will be a reference for further research activities, such as PLD process optimization, Active N gas application and Substrate heat treatment.

Keywords
PLD process – Coating material – Coating layer – Nanoparticle

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/Qc3wRqzn269r

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
Dhewa Edikresnha

Institutions
a)Departement of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesa 10, Bandung 40132, Indonesia

b)Research Center of Bioscience and Biotechnology, Institut Teknologi Bandung, Jalan Ganesa 10, Bandung 40132, Indonesia

c)Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Jalan Ganesa 10, Bandung 40132, Indonesia

Abstract
Electrospinning was employed to produce composite fibers mat consisting of PVP (polyvinylpyrrolidone)/CA (Cellulose Acetate) and Garlic Extract. The electrospun nanofiber mats for all variations show uniform and beaded free fibers. The average fiber diameter of composite fiber decreased along with the increasing applied voltage. The broad FTIR peak representing the stretching vibrations of O-H in hydroxyl groups of phenols and the sharp peak at 1014 cm-1 is the characteristic peak of garlic extract, which indicates the existence of S=O group and proving the presence of organosulfur compounds such as alliin, allicin dan diallyl disulfide. The characteristic peak shifted to a higher wavenumber after being synthesized into fibers. During the electrospinning process, the condition of cone jet in the tip of the needle was recorded and it was confirmed that when the applied voltage was from 12 to 14 kV there is intermittent squirt of solution indicating that the removal rate of the solution due to the applied voltage is smaller than the feed rate of solution. The concentration of garlic extract in the fibers was also examined and it was found that fibers with larger diameter contained larger concentration of garlic extract.

Keywords
Nanofibers, Polyvinylpyrrolidone, Cellulose Acetate, Garlic Extract, Electrospinning, Composite,

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/jq3T7CPFEGLM

Corresponding Author
Rakhmawati Muliana Putri

Institutions
a) Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
*) ferry[at]fi.itb.ac.id
b) Department of Chemistry, Universitas Pertamina, Jalan Teuku Nyak Arief, Simprug, Jakarta 12220, Indonesia
c) National Center for Sustainable Transportation Technologi, Istitut Tekniologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
d) Research Center for Nanosciences and Nanotechnology (RCNN), Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia

Abstract
Polyethylene oxide (PEO) is a polymeric material that has been widely used as solid polymer electrolytes (SPEs) for all-solid lithium ion battery (LIB) due to its excellent chemical stability. However, its low ionic conductivity at room temperature can be a significant problem that hampers the performance of the LIBs. Polyvinyl alcohol (PVA), due to its amorphous structure, is one of the polymers that is expected to improve the ionic conductivity of SPEs. In this study, we added polyvinyl alcohol (PVA) as a composite polymer to PEO based SPEs, with a varied amount of LiOH. The homogeneous solution was cast to form a thin and transparent SPE membrane. Characterization by X-Ray Diffraction (XRD) revealed the semi-crystalline properties of all samples. Ionic conductivity of SPEs composites was determined through AC impedance measurement using Electrochemical Impedance Spectroscopy (EIS). Among all samples that were studied, the sample with 4 wt. % LiOH revealed the highest ionic conductivity that reached 2.18 × 10-5 S.cm-1 at room temperature.

Keywords
lithium ion batteries (LIBs), solid polymer electrolytes (SPEs), polyethylene oxide (PEO), polyvinyl alcohol (PVA)

Topic
Minerals and Complex Materials

Link: https://ifory.id/abstract/pf4Y9zCnkmTW

Corresponding Author
Diah Miftahul Aini

Institutions
Biochemistry Research Division, Department of Chemistry, Bandung Institute of Technology
Jalan Ganesa No 10, Bandung 40132, Indonesia
*Corresponding author: rukman[at]chem.itb.ac.id

Abstract
Exopolysaccharide (EPS) is a straight/branched biopolymer consisting of sugar units and their derivatives. This sugar unit consists of glucose, galactose, mannose, N-acetylglucosamine, N-acetyl galactosamine, rhamnose, and fructose. EPS is very interesting biomaterial to be studied because it has many advantages such as nontoxic, water soluble, biodegradable and has many applications. EPS has been widely applied in various industrial fields, such as in the food industry, which is used as an emulsifier in cheese, bread, and milk-based production; while in pharmaceuticals industries, it has been used as a material for drug delivery system; and in bioindustry, it is used for enzyme immobilizer. In this study, EPS-producing halophilic bacteria have been screened from a salty lake Gili Meno Lombok, NTB, Indonesia. This study aims to perform a selection of a potential EPS-producing halophilic bacterium, identify its bacterial species, production of EPS and the application of EPS as a nanomaterial for protein immobilization. The EPS produced by the isolates from the selection above was verified by FTIR and NMR spectroscopy techniques. The results of the structure characterization showed that EPS produced by one Gili Meno bacterial isolate was inulin. This potential inulin producing bacterium closed to Salinivibrio costicola based on its16s rDNA sequence and the result of phylogenetic analysis so that it was named in this study as Salinivibrio costicola GM01. Inulin produced by this bacterium was used as a medium for protein immobilization in the form of nanoparticles. The immobilized protein target was lipase. The efficiency of lipase immobilized on nanoparticles were 81%. The SEM image of lipase-inulin nanoparticles showed spherical morphological shape with the diameter about 218−886 nm according to particle size analyzer (PSA) measurement. The zeta potential of the nanoparticle was about +0.03 mV. The respective lipase activity before and after the immobilization was 0.36 ± 0.010 units/mg and 0.28 ± 0.002 units/mg. These results showed that the inulin-based nanoparticle can provide compatible environment for lipase since its activity can be maintained about 80%.

Keywords
Inulin, nanoparticles, immobilization enzymes, Salinivibrio costicola GM01, halophilic bacteria, Gili Meno Lombok

Topic
Nano Science and Technology

Link: https://ifory.id/abstract/pQ7KPk8erCcB