Zr-MOF/MXene composite for enhanced photothermal catalytic CO2 reduction in atmospheric and industrial flue gas streams
Meng Yang, Feng Yue, Shuo Zhang, Lingji Zhang, Cong Li, Mengke Shi, Yongpeng Ma, Mario Berrettoni, Xiaojing Zhang, Hongzhong Zhang
Abstract
In this study, a novel composite was engineered by integrating Zr-MOF (NH 2 -UIO-66) with MXene layers through electrostatic self-assembly. Under simulated sunlight and at 80 °C, this composite material achieved nearly complete conversion of low-concentration atmospheric CO 2 to CO and CH 4 without additional sacrificial agents or alkaline absorption liquids, marking one of the few reports demonstrating near-complete reduction of low-concentration CO 2 directly from the air. For high-concentration CO 2 in industrial flue gas, the composite utilized residual heat at 80 °C without additional energy input, exhibiting excellent CO 2 reduction efficiency with CO and CH4 production rates of 127 μmol·g -1 ·h -1 and 330 μmol·g -1 ·h -1 , respectively, resulting in a total production rate 4.76 times higher than that in the air. Compared to most reports on thermocatalytic CO 2 reduction (>300 °C), this material shows significant advantages below 100 °C. The performance improvement is attributed to the introduction of Zr-MOF, which provides additional active sites and reduces activation energy. Additionally, the localized surface plasmon resonance (LSPR) effect of MXene facilitates the migration of thermal charge carriers to Zr 4+ sites within the MOF. Density Functional Theory (DFT) calculations validate these findings. Overall, Zr-MOF/MXene composite holds potential for reducing CO 2 in air and industrial settings, advancing energy conversion and environmental management.