N-doped Co3O4 catalyst with a high efficiency for the catalytic decomposition of N2O

A series of defective N-doped Co3O4 catalysts, N-Co3O4-x (x = 0.002, 0.01, 0.05, 0.15, and 0.25), were prepared by a facile graphitic carbon nitride (g-C3N4)-modified sol-gel method, and their catalytic behaviors for N2O decomposition reaction were evaluated. The activity tests indicated that all the N-Co3O4-x catalysts showed superior activity than the pristine Co3O4, and N-Co3O4-0.05 exhibited the best activity with 100% N2O conversion at a reaction temperature of 380 degrees C, ca. 160 degrees C lower than that of Co3O4. N-Co3O4-0.05 also showed high catalytic activity and stability in the presence of impurity gasses (O-2, NO, and/or H2O) at varying reaction conditions. Based on the employed systematic characterization techniques, the successful doping of N atoms into Co3O4 was confirmed. The N-doping facilitated more defective structures (namely oxygen vacancies), surface Co2+, and basic sites on Co3O4. In addition, N-doping contributed to enlarging the surface area, improving the electron donation ability of Co2+, enhancing the redox property of Co3O4, and weakening the Co-O bond. All these factors promoted the performance of N-Co3O4-0.05 for N2O decomposition. This work provides a simple strategy to construct advanced N-doped Co3O4 material for N2O decomposition applications and other catalytic reactions.

Automated summary

The study prepared a series of defective N-doped Co3O4 catalysts using a facile method and confirmed the successful doping of N atoms into Co3O4. Among them, N-Co3O4-0.05 exhibited the best performance in N2O decomposition reaction, attributed to the promotion of defective structures and oxygen vacancies, as well as the enhanced redox properties of Co2+ and Co3O4 by N doping.