Decavanadate Supported\non Carbon Nitride Nanosheets\nas Photocatalysts for Selective C–H Bromination of Arenes Using\nKBr

The photocatalytic bromination of arene C–H bonds\nis a crucial\nand sustainable transformation in organic synthesis chemistry. However,\ntraditional methods suffer from low efficiency, poor selectivity,\nand environmental concerns of bromine sources. Herein, we report a\ndecavanadate-modified graphite nitride carbon catalyst (V<sub>10</sub>-g-C<sub>3</sub>N<sub>4</sub>) that exhibits remarkable performance\nin the bromination of arene, utilizing nontoxic KBr as a bromine source\nunder visible-light irradiation. The “electron sponge”\nproperty of decavanadate in catalysts not only enhances catalytic\nactivity by suppressing the recombination of photogenerated carriers\n(electrons and holes) but also improves the activation of molecular\noxygen via single-electron transfer (SET), further enhancing catalytic\nefficiency. In addition, the electrostatic interaction between decavanadate\nand graphite nitride carbon exhibited high stability and activity\nafter five cycles, without a significant decrease. g-C<sub>3</sub>N<sub>4</sub> primarily absorbs substrates through π–π\ninteractions, while decavanadate offers Lewis-acid-type anchoring\nsites for O<sub>2</sub>, enabling the activation of both substrates\nand O<sub>2</sub> through the SET process. Fluorescence quenching,\nradical trapping, and electron paramagnetic resonance (EPR) experiments\nhighlight the pivotal importance of holes in enhancing substrate activation,\nwhile underscoring the crucial role of electrons in activating O<sub>2</sub> to <sup>•</sup>O<sub>2</sub><sup>–</sup>. This\nwork provides insights into the interaction between the decavanadate\nand organic semiconductor, enabling light-induced molecular transfer\nin green and sustainable chemistry.