Successive performance enhancement on a Ge-Ti codoped α-Fe2O3 with AlOOH modification photoanode for photoelectrochemical water splitting

The poor charge separation efficiency is the main limiting factor of the alpha-Fe2O3 photoanode for photoelectrochemical water splitting. In this study, we have discovered that the incorporation of Ge-Ti codoping and AlOOH modification strategies can greatly enhance the charge separation efficiency of the alpha-Fe(2)O(3 )photoanode. By introducing the Ti element, which possesses high conductivity, and further enhancing the charge transfer through Ge doping, we have achieved a synergistic inhibition of charge recombination in the Ge-Ti codoped alpha-Fe2O3. Additionally, the introduction of AlOOH through modification has led to an increase in the interface band bending, thereby enhancing charge separation by elevating the Fermi band level. Furthermore, through the secondary growth (shorted as SG) of undoped alpha-Fe2O3 and the incorporation of a NiFeO(x )cocatalyst, we have successfully adjusted the surface states and reduced the onset potential. Through the collaborative efforts of Ge-Ti codoping, SG, AlOOH modification, and NiFeOx catalysis, we have sequentially optimized the performance of the alpha-Fe2O3-based photoanode, resulting in an impressive photocurrent density of 3.46 mA cm(-2 )at 1.23 VRHE, as well as a low onset potential of 0.65 VRHE.

Automated summary

In this study, the poor charge separation efficiency of the alpha-Fe2O3 photoanode for photoelectrochemical water splitting was greatly enhanced through Ge-Ti codoping, AlOOH modification, secondary growth, and incorporation of a NiFeOx cocatalyst. The optimized photoanode exhibited high photocurrent density and low onset potential.