Synthesis of ZnO nanomaterials with controlled morphology and their photoelectrochemical properties

Three morphologies of ZnO nanomaterials (ZnO-hand grenade, ZnO-rod and ZnO-particle) were synthesized via a facile hydrothermal method. The as prepared ZnO nanomaterials were used as photoelectrodes to fabricate dye sensitized solar cells (DSSCs). Of the three samples, ZnO-particle displays the highest photovoltaic conversion efficiency which can be attributed to the high surface area to absorb light more efficiently. Intensity modulated photocurrent spectroscopy (IMPS), and intensity-modulated voltage spectroscopy (IMVS) indicate that ZnO-rod provides superior electron transfer kinetics: fast electron transfer and long electron lifetimes with suppressed recombination.