Ligand denticity engineering modulates geometric structure and interfacial electronic properties of MOF-derived In2O3/ZrO2 for CO2 hydrogenation to methanol

In 2 O 3 -based catalysts are promising for CO 2 hydrogenation to methanol owing to their high thermal stability and intrinsic methanol selectivity. However, the limited CO 2 activation capability and severe particle agglomeration of pristine In 2 O 3 restrict reactant adsorption and interfacial reaction efficiency. Herein, we propose a facile ligand denticity engineering strategy to regulate the electronic and mesoporous structures of MOF-derived In 2 O 3 -based catalysts by tuning the denticity of aromatic polycarboxylate ligands (H 2 BDC, H 3 BTC, and H 4 BTEC). Combined experimental characterizations, molecular dynamics (MD) simulations, and density functional theory (DFT) calculations confirm that H 4 BTEC endows MOF precursors and the derived mesoporous oxides with superior CO 2 diffusion and medium-temperature adsorption capacity. The H 4 BTEC-induced compact framework affords small mesopores, rich In-O-Zr interfacial sites, and strengthened metal-support electronic interaction, promoting electron transfer from Zr to In. In situ DRIFTS reveals that the H 4 BTEC-tailored catalyst accelerates the hydrogenation of HCOO* intermediates while suppressing the accumulation of byproduct intermediates. As a result, BTEC-In 2 O 3 /ZrO 2 delivers 9.4 % CO 2 conversion and a methanol space–time yield (STY) of up to 277 mg·gcat −1 ·h −1 at 280 °C and 3 MPa, with excellent stability over 100 h. This work establishes a versatile ligand denticity engineering methodology for constructing defective In 2 O 3 -based heterostructures, and sheds fundamental mechanistic light on ligand-governed structural and electronic modulation for efficient CO 2 hydrogenation.