Platinum single-atoms anchored covalent triazine framework for efficient photoreduction of CO2 to CH4

Achieving maximum atom-utilization efficiency is desirable to facilitate the charge separation and CO2 activation for photocatalytic CO2 reduction. Herein, we report a well-defined positioned synthesis of Pt single atoms in ethylene glycol (EG)-modified covalent triazine framework (Pt-SA/CTF-1) via a photo-deposition method for efficient photoreduction CO2 to CH4 under visible light irradiation. The well-defined coordination structure of Pt-N(C) sites in the Pt-SA/CTF-1 catalyst has been probed by HAADF-STEM and EXAFS. Results show that Pt single atoms confined into CTF-1 not only improved CO2 adsorption and activation but also accelerated the separation and transfer of photogenerated carriers in CTF-1. Consequently, Pt-SA/CTF-1 exhibited superior photoactivity and stability, which significantly surpass the Pt nanoparticles-based CTF-1, affording CH4 as the main reduction product. This work showcases an operable avenue to develop single-metal-atom photocatalysts and a mechanistic insight into photoreduction of CO2 by CTF-based composite.

Automated summary

This study presents an efficient photocatalytic CO2 reduction method by synthesizing Pt single atoms in a covalent triazine framework, resulting in high CH4 production. The presence of Pt single atoms improves CO2 adsorption and activation, accelerating the separation and transfer of photogenerated carriers, demonstrating superior photocatalytic performance and stability.