Rapid Joule heating synthesis of Pt clusters on C3N4 with abundant nitrogen vacancies for highly-efficiently photocatalytic H2 production

Solar-driven photocatalytic water splitting for hydrogen production was an essential way to simultaneously solve the energy crisis and environmental pollution problems. C3N4 was a promising substrate for photocatalytic hydrogen production. Herein, we prepared Pt nanoclusters anchored on C3N4 with nitrogen vacancies (Pt/NV-CN) using a rapid Joule heating method. Compared with the traditional calcination method, the Joule heating method not only shortened the preparation time, but also significantly increased the number of reactive sites and further enhanced the photocatalytic activity. Experiments and theoretical calculations confirmed that there was a rapid charge transfer between the metal (Pt) and the substrate (C3N4), and the dual active sites (i.e. nitrogen vacancies and Pt clusters) could decrease the hydrogen adsorption energy. Therefore, as-prepared Pt/NV-CN exhibited excellent hydrogen production activity with a production rate increased from 0 (for pristine C3N4) to 323.90 μmol/h/g, which was also greatly higher than that of Pt/CN-d-VN obtained by traditional tube furnace (97.08 μmol/h/g). This work provided a new method to fabricate the nitrogen vacancies and load Pt clusters onto C3N4 for highly-efficiently photocatalytic H2 production.