Defective h‑BNs-Supported\nPd Nanoclusters:\nAn Efficient Photocatalyst for Selective Oxidation of 5‑Hydroxymethylfurfural

5-hydroxymethylfurfural (HMF) is one of the most promising\nbiomass-based\nchemicals that is used to produce many kinds of important compounds.\nEspecially, the selective conversion of HMF to 5-hydroxymethyl-2-furancarboxylic\nacid (HMFCA), an important chemical feedstock, has high industrial\nsignificance but is technically challenging. In this study, we present\na high-performance photocatalyst for selective oxidation of HMF to\nHMFCA. By integrating an ultrasmall amount of palladium (Pd) nanoclusters\n(1.12‰ in weight) on defective hexagonal boron nitride nanosheets\n(Pd/defective h-BN nanosheets (dh-BNs)), outstanding photocatalytic\nperformance can be achieved, resulting in up to a 95% HMF conversion\nratio with an 82% HMFCA selectivity. The performance is considerably\nhigher than that of pristine dh-BNs and Pd on defect-free h-BNs. More\nimportantly, this Pd/dh-BNs catalyst maintains a high catalytic activity\nafter eight cycles, demonstrating robust catalytic stability. Density\nfunctional theory calculations indicate that Pd/dh-BNs can lower the\nenergy barrier for HMF oxidation and facilitate the desorption of\nHMFCA, which contributes to the high selectivity catalytic performance.\nThis study not only introduces a promising photocatalyst for sustainable\nchemical transformations but can also provide valuable insights into\nthe design of advanced photocatalytic material for biorefinery applications.