In-situ template etching synthesis of BiON/BiOCl0.9I0.1 heterojunction for photocatalytic degradation of tetracycline

Hierarchical heterostructures have emerged as promising candidates for the efficient photocatalytic degradation of antibiotics owing to their matched energy levels and tunable absorption bands. Herein, we report the facile synthesis of a heterojunction photocatalyst composed of basic bismuth nitrate (BiON) and BiOCl0.9I0.1 using a simple room-temperature hydrolysis method. Our results demonstrate that the BiON/BiOCl0.9I0.1 composite exhibits superior photodegradation performance compared to pure-phase materials owing to the catalytic enhancement at the heterointerface and the effective separation of the photogenerated carriers. Moreover, the unique three-dimensional microsphere morphology of the synthesized composite enhances its specific surface area and light absorption, further enhancing its photocatalytic activity. In the tetracycline (TC) photodegradation reaction as a model reaction, the catalyst could degrade 88% of TC in just 25 min. Overall, this work provides a promising strategy for the facile and low-cost synthesis of heterogeneous photocatalytic degradation materials.