Three birds, one-stone strategy for synthesis of hierarchically arrayed defective MnCo2O4@NF catalyst for photothermal preferential oxidation of CO in H2-rich streams

A novel strategy with the three birds, one stone effect has been proposed to enhance the catalytic performance of cobalt manganese spinel catalysts for photothermal CO-PROX in H2 streams. The approach involves fabri-cating hierarchically arrayed defective MnCo2O4@ Nickel foam (NF) through a simple hydrothermal post-treatment and partial recrystallization process. Three synergetic effects were induced by the hydrothermal posttreatment of MnCo2O4: (i) the creation of a hierarchically arrayed morphology that strengthens light ab-sorption and photo-to-thermal conversion, supported by finite-element method (FEM) simulations; (ii) the increased vacancy structures to alleviate significant electron-hole recombination; and (iii) abundant oxygen vacancy to facilitate oxygen adsorption and activation. These effects result in the unique hierarchically arrayed morphology and superior structural properties of MnCo2O4 spinel, which significantly enhances the photo-thermal synergism and catalytic activity of MnCo2O4@NF in photothermal CO-PROX driven by simulated solar light. This work provides a simple and facile strategy for developing hierarchical and defective MnCo2O4 spinel photothermal materials.

Automated summary

A novel strategy of fabricating hierarchically arrayed defective MnCo2O4@Ni foam catalysts has been proposed to enhance the catalytic performance for photothermal CO-PROX. The strategy generates three synergistic effects, including strengthened light absorption and photo-to-thermal conversion, alleviated electron-hole recombination, and facilitated oxygen adsorption and activation. These effects greatly improve the catalytic activity of MnCo2O4@NF in photothermal CO-PROX driven by simulated solar light. This work provides a simple and facile strategy for developing hierarchical and defective MnCo2O4 spinel photothermal materials.