Interfacial electron transfer mechanisms in bithiophene sensitized TiO2 based solar cells

Kinetic studies at Ti01/bithiophene/electrolyte interfaces were conducted, and their parameters to the solar cell functions were related. The solar cell based upon the bithiophene sensitised Ti02 films resulted in the maximum IPCE of approximately 25 % at 400 nm. Comparison of emission studies between the bithiophene adsorbed Ti01 and Ah03 revealed the electron injection from the excited bithiophene into the Ti02 with the efficiency of nearly I 00 %. The charge recombination between the bithiophene cation and the electron in the Ti02 appeared to be fast with a half decay time of 70 J.lS in comparison to the ruthenium dye sensitized Ti02 film (-1 ms). The bithiophene regeneration rate with the half time of 20 J.lS was slightly faster, clarifying the inferior photocurrent performance