Construction of Low‐Cost Z‐Scheme Heterostructure Cu 2 O/PCN for Highly Selective CO 2 Photoreduction to Methanol with Water Oxidation

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2021-11, Vol.17 (44)
• Main Authors: Tian, Zhi‐Yuan, Kong, Li‐Hui, Wang, Ye, Wang, Hong‐Juan, Wang, Yu‐Jie, Yao, Shuang, Lu, Tong‐Bu, Zhang, Zhi‐Ming
• Format: Article
• Language: English
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202103558

Solar‐driven CO 2 reaction with water oxidation into alcohols represents a promising approach to achieve real artificial photosynthesis. However, rapid recombination of photogenerated carriers seriously restricts the development of artificial photosynthesis. Herein, a facile method is explored to construct low‐cost Z‐Scheme heterostructure Cu 2 O/polymeric carbon nitride (PCN) by in situ growth of Cu 2 O hollow nanocrystal on PCN. The protective PCN layer and Z‐schematic charge flow can make robust Cu 2 O/PCN photocatalysts, and the spatial separation of electrons and holes with high redox potentials of E CB (−1.15 eV) and E VB (1.65 eV) versus NHE can efficiently drive CO 2 photoreduction to methanol in pure water, which is further confirmed by DFT calculation. The Z‐scheme heterostructure Cu 2 O/PCN exhibits a high methanol yield of 276 µmol g −1 in 8 h with ca. 100% selectivity, much superior to that of isolated Cu 2 O and PCN, and all the reported Cu 2 O‐based heterostructures. This work provides a unique strategy to efficiently and selectively promote the conversion of CO 2 and H 2 O into high‐value chemicals by constructing a low‐cost Z‐scheme heterostructure.