High adsorption and photocatalytic degradation abilities of amorphous Ta2O5 nanospheres under simulated solar light irradiation

Abstract

In this study, the crystallized and amorphous Ta2O5 nanospheres were successfully synthesized by a simple alcohol-thermal reaction. The particle sizes of amorphous Ta2O5 nanospheres were controlled by adjusting the PVP amount in the synthetic system. The removal abilities of the Ta2O5 towards organic dyes were assessed by measuring the adsorption and the photocatalytic degradation performance towards methylene blue (MB) under dark condition and simulated solar light irradiation, respectively. The results indicate that the amorphous Ta2O5 prepared with 1:5 PVP (a-Ta2O5 5PVP) exhibited extremely high adsorption abilities and photocatalytic degradation performances, compared to the crystallized and other amorphous Ta2O5 nanospheres. The excellent MB removal ability of a-Ta2O5 5PVP can be attributed to high specific surface area, extra O vacancies, enhanced visible light absorption, more photo-generated electrons and low charge transfer resistance. This study may shed light on a simple but low-cost preparation strategy for amorphous Ta2O5 nanospheres suitable for the future practical application on wastewater treatment and provide deep insights on the underlying reasons for the high removal performance to organic dyes.