Annealing Temperature Effect of ZnO Seed Layer on Integrated Photosupercapacitor Performance

Abstract

Photosupercapacitor is an integrated device for harvesting and storing solar energy into electrical energy. Photosupercapacitor is constructed by solar cell and supercapacitor. In the solar cell with DSSC type, one of the influential variables is photoanode performance. The photoanode with ZnO layer plays a role in light absorption, charge mobility, and electrical properties, which are influenced by crystal structure and nanoscale morphology. One of nanoscale morphology of ZnO that widely used is nanorods. This work is focussed to investigate the effect of annealing temperature on seed layer ZnO to growth nanorods shape in photoanode of photosupercapacitor and its performance. The seed layer ZnO nanoparticle was deposited onto FTO substrate by a screen printing method. The ZnO nanorod was grown by dippin FTO/ZnO in solution (Zinc nitrate, HMT, and DI water) under 100 °C. The photosupercapacitor was constructed by DSSC and ZnO symmetric supercapacitor which integrated by using aluminum foil substrate. The annealing temperature on ZnO nanoparticles affected on increasing crystal size of ZnO seed. All of the samples show ZnO wurtzite phase with the highest peak located on the hkl plane (101), but ZnO nanorod growth to hkl plane (100). The DSSC part efficiency produced around 0.874%. The resulting efficiency of photosupercapacitor is around 0.549%. The annealing temperature causes the value of specific capacitance to decrease, because of decreasing DSSC performance.