Lattice Strain-Induced d-p Orbital Hybridization Stabilizes Frustrated Lewis Pairs for Ultra-Stable CO2 Hydrogenation to Methanol

Abstract

Frustrated Lewis pairs (FLPs) offer a powerful platform for CO2 activation, yet their practical implementation in heterogeneous catalysis is limited by poor thermal stability at high temperatures. Here, we propose a defect-mediated lattice strain strategy to stabilize surface FLPs that achieve efficient CO2 hydrogenation to methanol. Systematic theoretical screening of heteroatoms with ionic dimensions matching that of Ce4+ reveals that Zr-doping-induced lattice strain stabilizes surface hydroxyl via the precise manipulation of Ce 5d-O 2p orbital hybridization behaviors, which ultimately sustains abundant thermally persistent FLPs. Notably, the synthesized FLP-enriched CeO2 compounded with Cu exhibits a markedly enhanced methanol space-time yield of 361.5 g·kgcat–1·h–1 for 150 h at 260 °C, more than doubling that of the unstrained analogue without Zr doping. Comprehensive mechanistic investigations further elucidate that the stable FLPs facilitate the charge-polarization-driven CO2 activation toward adsorbed CHO3* intermediates. Meanwhile, these FLP sites cooperate with tailored Cu species to construct a dual-active-site architecture capable of simultaneously activating CO2 and cleaving H2, thereby efficiently driving methanol synthesis via the formate-mediated pathway. This work establishes lattice strain as a key physicochemical lever for controlling FLPs stability and functionality, unlocking promising avenues for high-temperature FLP-enabled catalysis.