Influence of Successive Zirconium and Beryllium Codoping Strategies on Advancing Bulk and Surface Properties of Hematite Photoanodes for Boosting Photoelectrochemical Water Splitting

Photoelectrochemical(PEC) water splitting activity ofFe(2)O(3) is restricted by the rapid recombinationof photocarriersboth in bulk and on the surface and slack water oxidation kinetics.Herein, this work describes a method for designing and constructinga Fe2O3 photoanode by sequential in-situ and ex-situ incorporation of dopants for an effectivePEC water splitting strategy. In-situ Zr doping canbe used to improve the bulk conductivity of the photoanode by augmentingthe majority carriers while generating surface defects that limiteffective water oxidation at the photoelectrode/electrolyte interface.Therefore, the main emphasis of this study is on ex-situ codoping with Be, which boosts the surface charge transfer properties via the passivation of surface-trapping states, thus leadingto effective hole migration to the electrolyte. As a consequence,the Zr/Be codoped Fe2O3 photoanode (Zr/Be-HT)attained an 83% improved photocurrent density (1.92 mA/cm(2)) than that of bare-Fe2O3 at a water oxidationpotential of 1.23 V vs. RHE. Mott-Schottkyplots, electrochemical impedance spectroscopy, a transient time constant,and bulk and surface charge separation efficiency evaluations wereconducted to comprehend the functions of Zr and Be dopants. Finally,the Co-Pi cocatalyst-coated Zr/Be-HT photoanode produced 33.75and 17.76 & mu;mol/h H-2 and O-2 gases, respectively,at 1.23 V vs. RHE. This codoping strategy could leadto a more sustainable and efficient method for producing hydrogenfuel.

Automated summary

In this study, a Fe2O3 photoanode was designed and constructed by sequential in-situ and ex-situ doping to effectively improve the photoelectrochemical water splitting activity. The in-situ Zr doping improved the bulk conductivity and generated surface defects, while the ex-situ Be doping enhanced the surface charge transfer properties. The Co-Pi cocatalyst-coated Zr/Be-HT photoanode achieved substantial hydrogen and oxygen gas production, making this codoping strategy a promising method for sustainable and efficient hydrogen fuel production.