Decorating Cu2O photocathode with cu/Al bimetallic layer for enhanced photoelectrochemical water splitting

In this work, we reported a reasonable, simple, and low cost strategy that Cu2O is decorated with Cu layer and Al layer to realize the improvement of photoelectrochemical (PEC) performance. The results indicate that the Cu/Al layer that has surface plasmon resonance (SPR) effect inherits both properties of which Cu has high conductivity and Al could form thin Al2O3 layer to hinder Fermi-level pinning to accelerate the transfer of photoinduced electron-hole pairs. With the synergistic effect of Cu and Al, Cu/Al/Cu2O photocathode displays a higher photocurrent density (-2.16 mA/cm(2) at 0 V vs RHE), which is 3.7 times as high as the pure Cu2O. Thus, loading bimetallic is believed to be an effective strategy and could inspire interest in continuing to explore novel and effective bimetallic catalysts for PEC water splitting.

Automated summary

In this study, a reasonable, simple, and low-cost strategy was developed to enhance the photoelectrochemical performance of Cu2O by decorating it with Cu and Al layers. The Cu/Al layers exhibited surface plasmon resonance effect and combined the high conductivity of Cu with the ability of Al to form a thin Al2O3 layer, which hindered Fermi-level pinning and accelerated the transfer of photoinduced electron-hole pairs. The Cu/Al/Cu2O photocathode showed a significantly higher photocurrent density compared to pure Cu2O, indicating the effectiveness of bimetallic loading in improving PEC water splitting. This study inspires further exploration of novel and effective bimetallic catalysts.