g-C3N4 Loading Black Phosphorus Quantum Dot for Efficient and Stable Photocatalytic H2 Generation under Visible Light

Black phosphorus (BP) is an interesting two-dimensional material with low-cost and abundant metal-free properties and is used as one cocatalyst for photocatalytic H-2 production. However, the BP quantum dot (BPQD) is not studied. Herein, for the first time, BPQD is introduced as a hole-migration cocatalyst of layered g-C3N4 for visible-light-driven photocatalytic hydrogen generation. A high-vacuum stirring method is developed for BPQD loading without the dissociation of BP. The layered BPQD is coupled on the layered g-C3N4 surface to form a heterojunction structure. The 7% BPQD-C3N4 samples show similar time-resolved photoluminescence curves as 0.5% Pt-C3N4. The optimum hydrogen rates of the modified sample (7% BPQD-C3N4) are 190, 133, 90, and 10.4 mu mol h(-1) under simulated sunlight, LED-405, LED-420, and LED-550 nm irradiation, respectively, which are 3.5, 3.6, and 3 times larger than that of the pristine g-C3N4. Such low-cost layered system not only optimizes the optical, electrical, and texture properties of the hybrid materials for photocatalytic water splitting to generate hydrogen but also provides ideas for designing novel or easily oxidized candidates by incorporating different available materials with given carriers.