Enhanced photoconductivity of organic single-layered photoreceptor from bisazo/phthalocyanine composite

An organic single-layered photoreceptor (SLPR), where 2,5-bis(1″-azo-2″-hydroxy-3″-naphthoyl-o-chloroanide) oxazole/oxititanium phthalocyanine composite (O-bisazo/TiOPc composite) was used as the charge generation material (CGM) and N,N′-diethyl-4-aminobenzaldehyde-1-phenyl-1′-(α-naphthyl)-hydrazone (DENPH) as the charge transportation material (CTM), was prepared by the dip coating method and its photoconductivity was studied under the exposure of various wavelengths. It was found that such obtained SLPR showed much better photoconductivity than those from pristine O-bisazo or TiOPc and also better than the double-layered photoreceptor (DLPR) from the same composite. With the aid of UV-vis SEM, surface photovoltaic spectroscopy (SPS) and field-induced surface photovoltaic spectroscopy (FISPS) measurements, the enhanced photoconductivity was attributed to the formation of the charge transfer complex between O-bisazo and TiOPc as well as the much larger interfacial areas between CGM and CTM in the SLPR than those in the DLPR.