Heteronuclear Dual Single-Atom Catalysts for Ambient Conversion of CO<sub>2</sub> from Air to Formate
Shengliang Zhai, Jikai Sun, Lei Sun, Li Yang, Rui Tu, Shuchao Jiang, Tie Yu, Hao Wu, Chengcheng Liu, Zhen Li, Dong Zhai, Youyong Li, Guoqing Ren, Wei Deng
Abstract
Single-atom catalysts (SACs) can achieve the maximum metal atom utilization, which exhibit great potential for the chemical transformation of CO 2 . However, an isolated single active site is less satisfactory for catalyzing multiple molecule reactions involving CO 2 hydrogenation. In this work, we propose heteronuclear dual SACs composed of Pd and 3d transition metals supported by covalent triazine frameworks (CTFs). Among these catalysts, the optimized Pd 1 –Co 1 /CTF catalyst exhibits up to 84.6% conversion of the captured CO 2 from air into formate at 30 °C and 1 bar. The in situ DRIFT characterization and density functional theory calculations reveal that CO 2 in air is captured by the Et 3 N solution as bicarbonate, which is then hydrogenated into formate via the Pd 1 –Co 1 heteronuclear dual single atom with an energy barrier as low as 17.2 kcal/mol. The heteronuclear Pd and Co metal atoms act as the active site for H 2 activation and CO 2 adsorption, respectively, thus exhibiting enhanced activity for formate synthesis with a synergistic effect. These findings present an insight into the synthesis and application of heteronuclear dual SACs and pave an avenue for conversion of CO 2 in the air by heterogeneous catalysts.