Aerobic Conditions Enhance the Photocatalytic Stability of CdS/CdO x Quantum Dots

Photocatalytic H 2 production through water splitting represents an attractive route to generate a renewable fuel. These systems are typically limited to anaerobic conditions due to the inhibiting effects of O 2 . Here, we report that sacrificial H 2 evolution with CdS quantum dots does not necessarily suffer from O 2 inhibition and can even be stabilised under aerobic conditions. The introduction of O 2 prevents a key inactivation pathway of CdS (over‐accumulation of metallic Cd and particle agglomeration) and thereby affords particles with higher stability. These findings represent a possibility to exploit the O 2 reduction reaction to inhibit deactivation, rather than catalysis, offering a strategy to stabilise photocatalysts that suffer from similar degradation reactions.