Single Ru–P Site Catalyst Coupling N Sites in a Flexible Polymeric Framework for Efficient CO<sub>2</sub> Hydrogenation to Formate
Guangjun Ji, Cunyao Li, Benhan Fan, Guoqing Wang, Zhao Sun, Miao Jiang, Lei Ma, Yan Li, Yunjie Ding
Abstract
Hydrogenation of CO 2, an abundant C1 resource, into formate, is one of the most charming utilization routes of CO 2 . Herein, a series of single Ru–P site catalysts coupling N sites (denoted as Ru/P&N-POPs) were designed and applied in the highly effective hydrogenation of CO 2 to formate. The Ru (II) ions were firmly anchored and finely regulated by P sites in the polymeric skeleton, while the original N species surrounding single Ru–P active sites enriched and activated CO 2 . Besides, 13 C{1H} R-type RF irradiation and two-dimensional separated local field (2D R-SLF) experiments proved the good flexibility of P&N-POPs frameworks, which were beneficial for optimizing the orientation of functional sites and the synergy of abundant Ru–P active species and N species. As a result, a ca. 2000 h –1 TOF of CO 2 and at least 5 recycles were achieved in the formate synthesis under 393 K and 6.0 MPa (CO 2 /H 2 = 1:1). Multiple characterization methods including mass nuclear magnetic resonance, extended X-ray absorption fine structure, scanning transmission electron microscopy, in situ Fourier transform infrared, etc. were employed to reveal the mechanism for the catalytic performance of Ru/P&N-POPs.