Distinct Selectivity Control in Solar‐Driven Bio‐Based α‐Hydroxyl Acid Conversion: A Comparison of Pt Nanoparticles and Atomically Dispersed Pt on CdS

Solar‐driven photocatalytic lignocellulose conversion is a promising strategy for the sustainable production of high‐value chemicals, but selectivity control remains a challenging goal in this field. Here, we report efficient and selective conversion of lignocellulose‐derived α‐hydroxyl acids to tartaric acid derivatives, α‐keto acids, and H 2 using Pt‐modified CdS catalysts. Pt nanoparticles on CdS selectively produce tartaric acid derivatives via C−C coupling, while atomically dispersed Pt on CdS switches product selectivity to the oxidation reaction to produce α‐keto acids. The atomically dispersed Pt species stabilized by Pt−S bonds promote the activation of the hydroxyl group and thus switch product selectivity from tartaric acid derivatives to α‐keto acids. A broad range of lignocellulose‐derived α‐hydroxyl acids was applied for preparing the corresponding tartaric acid derivatives and α‐keto acids over the two Pt‐modified CdS catalysts. This work highlights the unique performance of metal sulfides in coupling reactions and demonstrates a strategy for rationally tuning product selectivity by engineering the interaction between metal sulfide and cocatalyst.