Ultra-photosensitive Y-type titanylphthalocyanine nanocrystals: Preparation and photoelectric properties

A microemulsion phase transfer method was developed to prepare Y-type titanylphthalocyanine nanocrystals (Y-TiOPc NCs) with an average diameter of 2.3 ± 0.8 nm. The purification and crystal transformation of TiOPc could be achieved in the one-step process by establishing a stable H 2 O/ o -dichlorbenzene microemulsion at high shear rate . The photoelectric characteristics of the ultrasmall Y-TiOPc NCs were evaluated by acting as the photoactive materials in organic photoreceptors , which afforded an impressive photosensitivity of E 1/2  = 0.064 μJ/cm 2 . The dispersion of the Y-TiOPc NCs in a solution of polyvinyl butyral , methylethylketone and cyclohexanone (PVB/MEK/CYC) showed excellent dispersibility (zeta potential: –50.0 mV) at least 60 days and suffered no photoelectric penalty. The excellent solvent-stabilized dispersibility mainly relied on electrostatic repulsion force resulting from the high charge-mass ratio due to ultrasmall particle size.