Improvement of photovoltaic properties in inorganic organic pigment particle heterojunction solar cell

Oxytitanium phthalocyanine (TiOPc) and zinc oxide (ZnO) pigments working as photoactive layers have been used to fabricate pigment particle hetero-junction structured solar cells. Performance test with this double layer cell shows an energy conversion around 0.15%. On the other hand, triple layered solar cell where TiOPc is sandwiched between H₂Pc (metal-free phthalocyanine) and ZnO shows an efficiency of about 2.4%. In both cases, good life test results have been obtained. Dependences of photovoltaic characteristics on the structure of double and triple layered devices, comprised of semiconductor pigment particles are shown and their potential for future application has been discussed.