The effect of Cobalt doping on The Photocatalytic Activity of Nanocomposites of ZnO Nanorods/Au Nanoparticles
Anita Eka Putri(a), Liszulfah Roza(b), Vivi Fauzia(a*)
a) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
*vivi[at]sci.ui.ac.id
b) Departement ofPhysicsEducation, Universitas Muhammadiyah Prof. Dr. Hamka, Jakarta Timur 12130, Indonesia
Abstract
The photocatalytic performance of Zinc oxide nanorods (ZnO NRs) still needs to be improved. One method that could be used to enhance the photocatalytic activity of ZnO NRs is by adding the noble metals nanoparticles and transition metals dopings. In this work,we synthesized nanocomposites of ZnO NRs/Au and Co-doped ZnO NRs/Au nanoparticles (NPs) by using ultrasonic spray pyrolysis and hydrothermal methods on the glass substrate. The microstructural, morphological, and optical properties of both nanocomposites were characterized by using XRD, FESEM and UV-Vis and PL spectroscopy. The photocatalytic performance was evaluated through the degradation of methylene blue (MB) under UV radiation. The results show that the pure ZnO NRs only degrades 28.8%, while the ZnO NRs/Au NPs could degrades 37.3%. Furthermore, the Co doped ZnO NRs/Au NPs also increases the degradation rate up to 46.5%. Based on these results, we conclude that the presence of Au on ZnO NR-s surface could enhance the photocatalytic activity due to its role as an electron sink that reduces the recombination rate of electrons and holes while the incorporation of Co in ZnO NRs could also enhance the number of crystal defects that beneficial for enhancing the photocatalytic activity of ZnO NRs.
Keywords: ZnO NRs/AuNPs nanocomposite; Co-doped; electron sink; photocatalytic activity; recombination
Topic: Material Science