Removing semiconductor-cocatalyst interfacial electron transfer induced bottleneck for efficient photocatalysis: A case study on Pt/CdS photocatalyst

Sunlight-driven photocatalytic hydrogen evolution represents a promising strategy to sustainable clean energy supply. This approach, however, is limited due to low rate even after replacing the sluggish oxygen evolution with efficient hole-extraction, because the very high barrier severely slows the supply of photogenerated electrons to the cocatalysts. Here, we bridge semiconductor-cocatalyst contact with metals that are of appropriate work function. This measure lowers the barrier for interfacial electron transfer by ∼800 meV in our demonstrated Pt/CdS photocatalyst. By this merit, the photocatalyst with intermediate metal delivers an unprecedented hydrogen evolution rate of 1.87 mmol dm −2  h −1 (37.4 mmol g −1  h −1 ) under sunlight (AM 1.5G, 100 mW/cm 2 ) and linearly increases to 18.39 mmol dm −2  h −1 (367.8 mmol g −1  h −1 ) by intensifying the illumination to 940 mW/cm 2 (AM 1.5G).