Continuous Tuning of the Au‐Cu2O Janus Nanostructures for Efficient Charge Separation

In photocatalysis, the Schottky barrier in metal-semiconductor hybrids is known to promote charge separation, but a core-shell structure always leads to charge build-up and eventually shuts off the photocurrent. Here, we show that the Au-Cu2O hybrid nanostructures could be continuously tuned, particularly when the Cu2O domains are single-crystalline. It is in contrast to the conventional systems where the hybrid configuration is mainly determined by the choice of materials. The distal separation of the Au-Cu2O domains in Janus nanostructures leads to enhanced charge separation and great improvement of the photocurrent. The activity of the Au-Cu2O Janus structures is 5 times higher than the core-shell structure, and 10 times higher than the neat Cu2O nanocubes. The continuous structural tuning allows study of the structure-property relationship, and optimization of the photocatalytic performance.