Hybrid zinc oxide:Cu-phthalocyanine bulk-heterojunction photovoltaic device†
Abstract
The hybrid bulk-heterojunction layer composed of Ga-doped ZnO (GZO) and Cu-phthalocyanine (CuPC) semiconductors was prepared by the simultaneous evaporation system involving the electron-beam evaporation for the Ga-doped ZnO and the thermal evaporation for the Cu-phthalocyanine. A hybrid CuPC/CuPC:GZO/n-ZnO photovoltaic device was constructed using electrodeposition of the n-ZnO layer followed by simultaneous evaporation techniques. The photo-assisted kelvin force microscopy (PKFM) measurements indicated that the increase in free carriers generated by the dissociation of excitons was induced by using the bulk-heterojunction structure due to the increase in heterointerface area. The CuPC/CuPC:GZO/n-ZnO photovoltaic device showed excellent rectification features and improved photovoltaic performance compared with the layered CuPC/n-ZnO photovoltaic device.