Exploring the ternary interactions in Cu\u2013ZnO\u2013ZrO2 catalysts for efficient CO2 hydrogenation to methanol

Yuhao Wang,Kongzhai Li,Shyam Kattel,Wengui Gao,Hua Wang,Ping Liu,Jingguang G Chen

doi:10.1038/s41467-019-09072-6

Abstract

The synergistic interaction among different components in complex catalysts is one of the crucial factors in determining catalytic performance. Here we report the interactions among the three components in controlling the catalytic performance of Cu–ZnO–ZrO2 (CZZ) catalyst for CO2 hydrogenation to methanol. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements under the activity test pressure (3 MPa) reveal that the CO2 hydrogenation to methanol on the CZZ catalysts follows the formate pathway. Density functional theory (DFT) calculations agree with the in situ DRIFTS measurements, showing that the ZnO–ZrO2 interfaces are the active sites for CO2 adsorption and conversion, while the presence of metallic Cu is also necessary to facilitate H2 dissociation and to provide hydrogen resource. The combined experiment and DFT results reveal that tuning the interaction between ZnO and ZrO2 can be considered as another important factor for designing high performance catalysts for methanol generation from CO2.

Highlights

The synergistic interaction among different components in complex catalysts is one of the crucial factors in determining catalytic performance
The EDS and transmission electron microscopy (TEM) analyses (Fig. 1b–d) suggest that Cu makes up the 3DOM framework, and the ZnO particles are well dispersed on the wall of the macropores
For the Cu/ZnO system, the Cu–ZnO interface or the Cu–Zn surface alloy are considered as the active sites for CO2 hydrogenation to methanol[3,5,6,7,24,28,29]

Summary

Introduction

The synergistic interaction among different components in complex catalysts is one of the crucial factors in determining catalytic performance. We report the interactions among the three components in controlling the catalytic performance of Cu–ZnO–ZrO2 (CZZ) catalyst for CO2 hydrogenation to methanol. The combined experiment and DFT results reveal that tuning the interaction between ZnO and ZrO2 can be considered as another important factor for designing high performance catalysts for methanol generation from CO2. The Cu/ZrO2 synergy is mainly attributed to the formation of Cu–ZrO2 interfacial sites, which may promote the adsorption of CO210,26, enhance the dissociation of H2 and spillover of atomic hydrogen[32,33], bind the key reaction intermediates (*CO2, *CO, *HCO, and *H2CO) for further conversion[27], and increase the turnover frequency[26]

Methods

Results

Conclusion