Hierarchical Pores Structured Inverse Opal-TiO₂-Bi₂WO₆ for Photocatalytic Tetracycline Elimination-Testing by Real-Time Monitor of Germination Rate and Growth Rate of Chinese Cabbage

A novel Inverse Opal-TiO₂-Bi₂WO₆ (ITB) with hierarchical pores structure was composed for tetracycline photodegradation, whose degradation effect was investigated by real-time monitor of germination rate and growth rate of cabbages. The three-dimensional hierarchical pores structure could contribute to a high surface area of catalysts, hence enhance adsorption sites for tetracycline. A Z-scheme heterojunction is proved to be formed between inverse opal structured TiO₂ (IO-TiO₂) and Bi₂WO₆, which could enhance carrier's separation and transfer efficiency to enhance tetracycline degradation activity. In addition, the possible photocatalytic mechanism was explored and proposed. Based on free radical trapping experiments, hydroxyl radicals (⋅OH) and oxygen anion free radicals (⋅O²⁻) play important roles in tetracycline photodegradation. This is the first work reported on real-time investigation of the effect of photocatalysts on crop germination rate and growth rate by decreasing tetracycline concentration.