Synthesis of NaNbxTa1-xO3/g-C3N4 composite photocatalyst for enhanced removal of organic dye

Water pollution has received much attention and constructing efficient catalysts to photodegrade the pollutants is a promising method. Herein, we reported that a novel composite catalyst, NaNbxTa1-xO3/gC3N4, exhibited high efficiency to degrade the model pollutant, methylene blue (MB), in ultraviolet light. The optimal catalyst was NaNb0.75Ta0.25O3/g-C3N4 (1:9), which degraded 99.6% of MB (10 mg/L) after 180 min of reaction. The superior photocatalytic activity was attributed to the formation of the Z-scheme heterojunction, which could suppress the recombination of the photogenerated electron-hole pairs and protect the high redox potentials simultaneously. Hydroxyl radicals (.OH) and superoxide radicals (.O2-) were found to be the dominant active free radicals in the reaction process and a possible photocatalytic mechanism over the catalyst was proposed accordingly. This work provides an efficient direction to fabricate composite photocatalysts and helps to overcome the shortcomings of a single catalyst. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Water pollution is a major concern and developing efficient catalysts for photodegrading pollutants is a promising approach. In this study, a novel composite catalyst, NaNbxTa1-xO3/gC3N4, showed high efficiency in degrading the model pollutant methylene blue (MB) under ultraviolet light. The optimal catalyst was NaNb0.75Ta0.25O3/g-C3N4 (1:9), which degraded 99.6% of MB (10 mg/L) after 180 minutes of reaction. The superior photocatalytic activity was attributed to the formation of a Z-scheme heterojunction, which suppressed the recombination of electron-hole pairs and protected high redox potentials simultaneously. Hydroxyl radicals (.OH) and superoxide radicals (.O2-) were identified as the dominant active free radicals in the reaction process.