Arrangement of band structure for organic-inorganic photovoltaics embedded with silicon nanowire arrays grown on indium tin oxide glass

Silicon nanowires (SiNWs) arrays grown vertically on an indium tin oxide glass substrate by the vapor liquid solid process are covered with poly (3-hexylthiophene) (P3HT) mixed with [6,6]-phenyl-C-60-butyric acid methyl ester (PCBM) to make into a hybrid solar cell. With proper control of the nanowire size and arrangement of the band structure suitable for charge carrier transport, the P3HT/SiNWs solar cell can have a much better energy conversion efficiency than the P3HT+PCBM solar cell. Poor band structure arrangement can lead to band barrier and enhanced electron-hole pair recombination and much lower efficiency even with more light absorption.