Search

BV/In 2 O 3 /FeNi photoanode was rational designed and constructed by impregnation annealing and electrodeposition method. A stable photocurrent of 4.0 mA cm−2 was achieved at 1.23 V RHE under AM 1.5 G (100 mW cm−2), which can be ascribed to the synergistic effect of heterojunction structure and cocatalyst loading. [Display omitted] Bismuth vanadate (BiVO 4) is a promising nanomaterial for photoelectrochemical (PEC) water oxidation. However, the serious charge recombination and sluggish water oxidation kinetics limit its performance. Herein, an integrated photoanode was successfully constructed by modifying BiVO 4 (BV) with In 2 O 3 (In) layer and further decorating amorphous FeNi hydroxides (FeNi). The BV/In/FeNi photoanode exhibited a remarkable photocurrent density of 4.0 mA cm−2 at 1.23 V RHE , which is approximately 3.6 times larger than that of pure BV. And the water oxidation reaction kinetics has an over 200% increased. This improvement was mainly because the formation of BV/In heterojunction inhibited charge recombination, and the decoration of cocatalyst FeNi facilitated the water oxidation reaction kinetics and accelerated hole transfer to electrolyte. Our work provides another possible route to develop high-efficiency photoanodes for practical applications in solar conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • A smart strategy, interface "repairing", was proposed to effectively boost the photogenerated charge separation. • BV/NiO x /CoFe achieves a remarkably photocurrent density of 4.58 mA cm−2 at 1.23 V RHE , which is more than three-fold higher than BV photoanode. • The interface charge recombination and intrinsic photocorrosion can be efficiently suppressed through "fast" hole transfer kinetics. Photoelectrochemical (PEC) water splitting is an attractive strategy to convert and store of intermittent solar power into fuel energy. However, the detrimental charge recombination of photogenerated electrons and holes severely limits its efficiency. Despite electrocatalyst loading can obviously improve the PEC conversion efficiency, current systems still suffer from high recombination owing to the surface states. Herein, an interface "repairing" strategy is proposed to suppress the recombination at the semiconductor/electrocatalyst interface. NiO x layer acts as an interfacial repairing layer to efficiently extract photogenerated charge carriers and eliminate the surface states via high hole-transfer kinetics rather than as a traditional electrocatalyst. As expected, the resulting repaired system yields an impressive photocurrent density of 4.58 mA cm−2 at 1.23 V (vs. RHE), corresponding to a more than three-fold increase compared to BiVO 4 (1.40 mA cm−2). Our work offers an appealing maneuver to improve the water oxidation performance for the semiconductor/electrocatalyst coupling system. [ABSTRACT FROM AUTHOR]

Temperature regulation can not only achieve "fast" surface catalytic reaction at solid/electrolyte interface but also obtain "high" interfacial charge transport kinetics at solid/solid interface. The desired photoelectrochemical performance can be achieved by temperature regulation, but the nature for this improvement remains a controversial topic. Herein, we employed BiVO 4 /CoO x as a typical model system, and explored the fate of photogenerated holes at the different interfaces among BiVO 4 /CoO x /electrolyte by means of intensity modulated photocurrent spectroscopy (IMPS), scanning photoelectrochemical microscopy (SPECM) and traditional electrocatalysis characterization methods. Systematic quantitative analysis of the kinetics of photogenerated holes transfer at the BiVO 4 /CoO x interface under illumination and surface water oxidation at the CoO x /electrolyte interface in the dark indicates that increasing temperature could not only enhance the surface catalytic reaction kinetics but also facilitate the interfacial charge transfer. As expected, the integrated system exhibited a remarkable photocurrent density of 3.6 mA cm−2 (1.23 V RHE , AM 1.5G, 45 °C), which is approximately 2.1 times higher than that of BiVO 4 /CoO x (15 °C). This work provides a promising strategy for achieving efficient photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]