Direct Air Capture and Photoconversion of CO <sub>2</sub> to Ethylene by Defect‐Tailored Cu <sub>3</sub> ‐Based Metal–Organic Frameworks
Yu He, Wen‐Yi Zheng, Yong Liu, Weng‐Da Zhang, Huan Pang, Jiangwei Zhang, Wang‐Kang Han, Zhi‐Guo Gu
Abstract
Abstract The development of efficient direct air capture (DAC) systems coupled with photocatalytic CO 2 conversion is still an appealing challenge. Here, we engineered a series of defective Cu 3 ‐based metal–organic frameworks (Cu 3 ‐MOFs) for integrated atmospheric CO 2 capture and in situ photoreduction. The defective Cu 3 ‐MOFs were constructed through selective removal of coordinated CO 3 2− from pristine MOFs with HCl etching, generating unsaturated Cu active sites for CO 2 harvesting, and the Cu 3 ‐MOFs demonstrated enhanced CO 2 capture kinetics and capacity that compared to their pristine counterpart. Remarkably, the captured CO 2 could be directly photoreduced to C 2 H 4 with an optimal production rate of 18.25 µmol·g −1 ·h −1 without additional photosensitizer or sacrificial agent. The experimental and theoretical results revealed that the defective sites not only facilitated CO 2 adsorption but also promoted C–C coupling of *CO intermediates, thereby enhancing C 2 H 4 production. This work provides deep insights for designing advanced materials toward direct air‐to‐fuel conversion.