Excessive use of fossil energy causes global warming and other environmental problems. To reduce the greenhouse effect, two major greenhouse gases-CO2 and CH4 as the feedback are used to produce syngas (CO and H2) by CO2-CH4 reforming technique (DRM). The key to DRM is the choice of catalyst. The catalyst for DRM reaction mainly consists of two parts: the active metal and the support, in which a suitable support plays an important role in promoting the reaction activity and stability. Currently, ZrO2 is considered as a promising catalyst support due to the presence of oxygen vacancies. However, studies on the effect of oxygen vacancies on the ZrO2 surface for CO2 adsorption and activation processes are still lacking.
A research group of Juntian Niu from Taiyuan University of Technology investigated the effect of oxygen vacancies for the adsorption and activation of CO2 on the surface ZrO2 by density functional theory (DFT) calculations. They found that the oxygen vacancies contribute greatly to both the adsorption and activation of CO2, and the essence lies in oxygen vacancies greatly facilitate the charge transfer from the ZrO2 surface to the CO2 molecule. Additionally, it was found that t-ZrO2 with the presence of oxygen vacancies is most favorable to the adsorption and activation of CO2 by the comparison of different ZrO2 crystalline phases.
The new findings elucidated the role of oxygen vacancies in CO2 adsorption and activation for the preparation of high-performance DRM reaction catalysts using ZrO2. Meanwhile, it provided guidance for the design of CO2 high-efficient catalysts at an atomic level.
These findings were published in Frontiers in Energy on February 28.
