LAUSR

The big challenging issues in photocatalytic H2 evolution are efficient separation of the photoinduced carriers, the stability of the catalyst, enhancing quantum efficiency and requiring photoinduced electrons enrich on photocatalysts' surface. Herein, Ti3C2 MXene quantum dots (QDs) possess the activity of Pt as co-catalyst in promotion the photocatalytic H2 evolution to form heterostructure with g-C3N4 nanosheets (NSs) (denoted as g-C3N4@Ti3C2 QDs). The photocatalytic H2 evolution rate of g-C3N4@Ti3C2 QDs composite with an optimized Ti3C2 QDs loading amounts (100 mL) is nearly 26, 3 and 10 times higher than pristine g-C3N4 NSs, Pt/g-C3N4, Ti3C2 MXene sheet/g-C3N4, respectively. The Ti3C2 QDs increase the specific surface area of g-C3N4 and boost the density of active site. Besides, metallic Ti3C2 QDs possess excellent electronic conductivity, causing the improvement of carrier transfer efficiency.