Facile preparation of functionalized and oxygen-deficient V2O5 nanosheets electrode as a versatile platform for biomimetic- and photoelectro-catalysis

In this study, we present a facile and scalable preparation of formamide-functionalized and oxygen-deficient V2O5 nanosheets (thickness: 30 similar to 40 nm) modified electrode (FTO|exf-V2O5) with promising peroxidase-like and photoelectrocatalytic activity. FTO|exf-V2O5 was prepared by the direct top-down exfoliation of the V(2)O(5)sub-micron plates (thickness: 300 -550 nm) modified electrode (FTO|micro-V2O5) in the presence of formamide as the exfoliation agent at mild conditions. Formamide molecules were found to adsorb on FTO|exf-V2O5 and serve as the active sites for the reduction of noble metal, which not only enables the application of FTO|exf-V2O5 for the recovery of noble metals but also allows further functionalization and electrocatalytic oxidation of V2O5. As compared with FTO|micro-V2O5, FTO|exf-V(2)O(5)had significantly higher oxygen vacancy (VO) content and exhibited remarkably enhanced peroxidase activity with an ultra-low Michaelis-Menten constant of 68.24 mu M and a high catalytic constant (or maximal turnover frequency) of 0.28 s(-1). Finally, FTO|exf-V(2)O(5)with lower dimension and higher V-O content showed improved kinetics of charge-transport and interfacial charge-transfer, resulting in the enhanced activity towards photoelectrocatalytic oxidation of water and methanol. This work opens a new avenue for the preparation of exfoliated 2-D material based platform for biomimetic catalysis and energy conversion.

Automated summary

In this study, a facile and scalable method for preparing formamide-functionalized and oxygen-deficient V2O5 nanosheets modified electrodes (FTO|exf-V2O5) with promising peroxidase-like and photoelectrocatalytic activity was presented. The FTO|exf-V2O5 was prepared by directly exfoliating V(2)O(5) sub-micron plates modified electrodes (FTO|micro-V2O5) using formamide as the exfoliation agent. The formamide molecules served as active sites for the reduction of noble metal, enabling the recovery of noble metals and further functionalization and electrocatalytic oxidation of V2O5. Compared with FTO|micro-V2O5, FTO|exf-V(2)O(5) exhibited significantly higher oxygen vacancy content and remarkably enhanced peroxidase activity, as well as improved charge-transport kinetics and interfacial charge-transfer, resulting in enhanced photoelectrocatalytic oxidation activity towards water and methanol. This work opens up new possibilities for the preparation of exfoliated 2-D materials for biomimetic catalysis and energy conversion.