ZnO/ZnS heterostructures for hydrogen production by photoelectrochemical water splitting

This work studies the photoelectrochemical behavior of novel ZnO/ZnS heterostructures obtained by means of anodization in water and glycerol/water/NH 4 F electrolytes with different Na 2 S additions under controlled hydrodynamic conditions. For this purpose different techniques such as Field Emission Scanning Electronic Microscopy (FE-SEM) with EDX, Raman spectroscopy and photoelectrochemical water splitting tests under standard AM 1.5 conditions have been carried out. The obtained results showed that the hydrodynamic conditions promoted an ordered nanotubular morphology which facilitates electron-hole separation and consequently, the photoelectrochemical activity for water splitting is enhanced. Additionally, the effect of glycerol in the anodization solutions seems to be beneficial for increasing the dark current photostability. ZnO/ZnS heterostructures anodized under stirring conditions and in glycerol/water electrolyte succeeded as being a photococatalyst for photoelectrochemical water splitting.