Fabrication of Integrated Copper‐Based Nanoparticles/Amorphous Metal–Organic Framework by a Facile Spray‐Drying Method: Highly Enhanced CO2 Hydrogenation Activity for Methanol Synthesis

We report on Cu/amUiO‐66, a composite made of Cu nanoparticles (NPs) and amorphous [Zr6O4(OH)4(BDC)6] (amUiO‐66, BDC=1,4‐benzenedicarboxylate), and Cu‐ZnO/amUiO‐66 made of Cu‐ZnO nanocomposites and amUiO‐66. Both structures were obtained via a spray‐drying method and characterized using high‐resolution transmission electron microscopy, energy dispersive spectra, powder X‐ray diffraction and extended X‐ray absorption fine structure. The catalytic activity of Cu/amUiO‐66 for CO2 hydrogenation to methanol was 3‐fold that of Cu/crystalline UiO‐66. Moreover, Cu‐ZnO/amUiO‐66 enhanced the methanol production rate by 1.5‐fold compared with Cu/amUiO‐66 and 2.5‐fold compared with γ‐Al2O3‐supported Cu‐ZnO nanocomposites (Cu‐ZnO/γ‐Al2O3) as the representative hydrogenation catalyst. The high catalytic performance was investigated using in situ Fourier transform IR spectra. This is a first report of a catalyst comprising metal NPs and an amorphous metal–organic framework in a gas‐phase reaction. We report on a first demonstration for a catalyst comprising metal NPs and amorphous MOF in a gas‐phase reaction. Cu/amorphous UiO‐66 exhibited 3‐fold catalytic activity for CO2 hydrogenation into methanol over Cu/crystalline UiO‐66. Amorphous UiO‐66 coating on Cu‐ZnO nanocomposites showed 1.5‐fold catalytic activity enhancement over that of Cu/amorphous UiO‐66.