Photoconduction and application of oxotitanium phthalocyanine dual-layeredthin films

The photo-conduction of oxotitanium phthalocyanine (TiOPc) and their applic ation as photo-generation carrier materials in dual layered photoreceptors were studied. The conductivities of the photo/dark conductions were 1.54 x 10(-12) and 1.23 x 10(-13) S/cm in the ohmic region (slope approximate to 1 ), and 6.73 x 10(-10) and 1.31 x 10(-12) S/cm in non-ohmic regions obtained from the photo/dark J-V characteristics at room temperature, respectively. The ratio of photo/dark conduction increases with increasing field, from m ore than one order of magnitude at field 1.30 x 10(2) V/cm to near three or ders of magnitude at 1.30 x 10(5) V/cm. The photoelectron properties of TiO Pc as photo-generation carrier material in the dual-layered photoreceptor w ere characterized by the use of corona dark charging and photo-discharging. The obtained data are listed in the following: the saturated surface dark potential V-0 = 630 V; dark decay rate R-d = 6.5 V/s, measured by average p otential decreases in the initial 2 s after dark decay; light sensitivity E -1/2 = 2.5 erg/cm(2), calculated from illuminating power E-L = 5 muW and ha lf photodecay time t(1/2) = 0.5 s; surface residual potential V-r = 25 V. ( C) 2000 Elsevier Science S.A. All rights reserved.