GRAPHENE-ZINC OXIDE NANOCOMPOSITE FOR SOLAR CELL APPLICATIONS

Abstract

ZnO nanowires was grown using two different solution based method. It was found that by using different pH in the growth solution, ZnO nanowire with different morphology was produced. The patterning of ZnO nanowires was successfully done on different substrates using photolithography technique. Variation in the pitch of the patterns and also the use of different growth solution are shown to control the desired nanostructures. Meanwhile, graphene oxide sheet as large as 60?m was produced based on modified Hummer?s method. A one-pot synthesis of rGO-ZnO composite has also been developed which reduces the GO and at the same time forms the rGO-ZnO nanoparticle composite, using mild and scalable conditions. ZnO aggregates and rGO-ZnO nanocomposites have also been successfully synthesised using photoreduction method. Lastly, the ZnO nanostructures and rGO-ZnO nanocomposites synthesised was incorporated into the design of photoanode of dye sensitized solar cell to boost the efficiency. An improved efficiency of 4.92% was achieved for patterned ZnO nanowire dye sensitized solar cell through enhanced light scattering and charge collection. However, the increase in efficiency of dye sensitized solar cell when graphene is incorporated has not been achieved. Further investigations need to be done to elucidate the ineffectiveness of as-synthesized graphene-ZnO nanocomposite for solar cell application.