CeO2/Cr2O3 direct Z-scheme heterojunction for photo-thermal synergistic catalytic isopropanol degradation and nitrogen fixation

A CeO2/Cr2O3 composite heterojunction material is prepared by the combination of a water bath method and a high temperature calcination method. The CeO2/Cr2O3 composite shows enhanced photo-thermal synergistic catalytic activity in comparison with single component Cr2O3 and CeO2. The photo-thermal catalytic nitrogen fixation rate of the CeO2/Cr2O3 composite is 21.0 times that of Cr2O3 and 11.7 times that of CeO2. The photo-thermal catalytic isopropanol degradation rate of the CeO2/Cr2O3 composite is 1.3 times that of Cr2O3 and 3.0 times that of CeO2. The improved catalytic activity of the CeO2/Cr2O3 composite is attributed to the following three points. The CeO2/Cr2O3 heterojunction exhibits a Z-scheme charge transfer mechanism, and the photo-generated carriers have a strong redox ability. There are abundant oxygen vacancies in the CeO2/Cr2O3 composite, which can form a new impurity level leading to the weakening of carrier recombination. The CeO2/Cr2O3 composite has a large specific surface area, which can provide more catalytically reactive sites. Moreover, the photo-thermal catalytic isopropanol degradation activity of CeO2/Cr2O3 has no significant decrease after four cycle experiments, proving its good stability. This study inspires the design and construction of efficient photo-thermal catalysts in the field of air purification and energy conversion.

Automated summary

A CeO2/Cr2O3 composite heterojunction material with enhanced photo-thermal synergistic catalytic activity and good stability has been prepared by a water bath method and a high temperature calcination method. It provides inspiration for the design and construction of efficient photo-thermal catalysts in the fields of air purification and energy conversion.