A Conformal Carbon Nanolayer Coated Fe2O3 Cocatalyst for the Promoted Activity of Plasma-Sputtered BiVO4 Photoanode

To simultaneously improve the hole extraction ability of the BiVO4 photoanode and accelerate the surface reaction kinetics, herein, a carbon nanolayer conformally coated Fe2O3 (C-Fe2O3) as oxygen evolution catalyst (OEC) is loaded on the H-2 plasma treated nanoporous BiVO4 (BVO(H-2)) surface by a hydrothermal reaction. It is found that the H-2 plasma induced vacancies in BVO remarkably increases the conductivity, and the C-Fe2O3 enables hole extraction from the bulk to the surface as well as efficient hole injection to the electrolyte. As a result, the C-Fe2O3/BVO(H-2) photoanode achieves a photocurrent density of 4.4 mA/cm(2) at 1.23 V vs. reversible hydrogen electrode (RHE) and an ABPE value of 1.5 % at 0.68 V vs. RHE, which are 4.8-fold and 13-fold higher than that of BVO photoanode, respectively.

Automated summary

By hydrothermal reaction, a carbon nanolayer conformally coated Fe2O3 (C-Fe2O3) as oxygen evolution catalyst (OEC) is loaded on the H-2 plasma treated nanoporous BiVO4 (BVO(H-2)) surface to simultaneously improve the hole extraction ability of the BiVO4 photoanode and accelerate the surface reaction kinetics. It is found that the H-2 plasma induced vacancies in BVO remarkably increases the conductivity, and the C-Fe2O3 enables efficient hole extraction and injection. As a result, the C-Fe2O3/BVO(H-2) photoanode exhibits significantly enhanced photocurrent density and ABPE value compared to the BVO photoanode.