Poly(triazine imide) Crystals for Efficient CO 2 Photoreduction: Surface Pyridine Nitrogen Dominates the Performance

作者：Feng Liu, Jing Deng, Bo Su, Kang‐Shun Peng, Kunlong Liu, Xiahui Lin, Sung‐Fu Hung, Xiong Chen, Xue Feng Lu, Yuanxing Fang, Guigang Zhang, Sibo Wang · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.4c06685 · 被引用次数：109 · 研究领域：Advanced Photocatalysis Techniques、Covalent Organic Framework Applications、CO2 Reduction Techniques and Catalysts

Polymeric carbon nitrides (PCNs), usually the melon phase, have been extensively applied as photocatalysts for CO 2 reduction; however, their performance is still unsatisfactory. The condensed allotrope, namely, poly(triazine imide) (PTI) with extended conjugation and a crystallized structure, indeed holds more favorable compositional and structural advantages for photocatalytic CO 2 reduction but remains to be fully exploited. Herein, hexagonal prism-shaped PTI crystals were synthesized and developed as a high-performance photocatalyst for CO 2 reduction. With Co(bpy) 3 2+ as a cocatalyst, the PTI crystals exhibit a CO evolution rate of 44 μmol h –1 (i.e., 1467 μmol g –1 h –1 ) with 93% selectivity, markedly superior to that of the melon counterpart. Moreover, PTI crystals manifest an apparent quantum efficiency of 12.9% at 365 nm, representing the state-of-the-art value by PCN photocatalysts for CO 2 -to-CO reduction without using noble metals. The surface pyridine N species of PTI are exposed as active sites to dominate CO 2 activation and conversion, which, together with the high crystallinity to facilitate charge separation and transport, endows high CO 2 reduction efficiency. In situ diffuse reflectance infrared Fourier transform spectroscopy determines the key intermediates during the CO 2 reduction reaction and, consequently, constructs the possible reaction mechanism.