Constructing the asymmetrically coordinated Pt single atoms by doping g-C3N4 support for enhanced photocatalytic plastic reforming for H2 evolution

Photocatalytic plastic reforming for H 2 production offers a promising eco-friendly strategy for waste resource upcycling, yet constructing efficient single-atom photocatalysts remains a challenge. Herein, we report a support doping strategy to tailor the coordination environment of single atoms, and develop a single-atom Pt decorated P-doped g-C 3 N 4 photocatalyst (Pt 1 /PCN). The Pt 1 /PCN featuring an asymmetric Pt N 3 structure exhibits a H 2 production rate of 2722.8 μmol g −1  h −1 , which is 17.3 times that of Pt/CN and 7.8 times that of Pt 1 /CN, and outperforms previously reported CN-based photocatalysts. Mechanistic studies indicate that the asymmetric Pt N 3 configuration enhances the internal electric field, effectively facilitating the separation of photogenerated charges. Meanwhile, the doped P atoms serve as electron donors to alleviate the electron deficiency of Pt sites, promoting the upward shift of the d-band center of Pt, thereby optimizing the reaction kinetics for H 2 evolution. More importantly, the practical applicability of Pt 1 /PCN is demonstrated by its excellent performance in outdoor photocatalytic plastic reforming for H 2 production. This work presents a rational design strategy for the construction of efficient single-atom photocatalysts and provides in-depth insights into the atomic-level mechanism of H 2 evolution.