Study on preparation and degradation performance of AI-Driven Bi₂O₃/ZIF-8 catalyst
AI驱动Bi₂O₃/ZIF-8催化剂的制备及其降解性能研究

摘要

本研究以水热法制备的ZIF-8为载体，通过原位负载Bi₂O₃前驱体，引入AI算法，合成了Bi₂O₃/ZIF-8复合光催化材料，并构建了“AI辅助制备—比例预测分析—降解条件优化”体系。采用AI正交实验设计，以水热温度（120~150℃）、反应时间（2~4 h）和Bi₂O₃理论负载量（10%~25%）为自变量，以降解率为响应值，建立二次多项式回归模型，确定最优参数为135℃、2.5 h、18%。模型预测值与实验值相对误差<5%。物相结构与微观形貌测试结果表明，ZIF-8凭借其大比表面积和优异的多孔结构，有效改善了Bi₂O₃纳米颗粒的分散性，大幅增加了复合材料的活性位点，使该材料具有更高的光催化活性。实验结果显示，当Bi₂O₃负载量为18%时，Bi₂O₃/ZIF-8材料的光催化活性达到最优，对10 mg/L四环素溶液的降解率可达81.9%；淬灭实验显示·O₂⁻、h⁺、·OH对降解的贡献率分别约为65%、22%、13%；同时，该催化剂经五次循环降解实验后，对四环素的降解率仍能维持在76.9%以上，展现出良好的重复使用性能，这主要得益于ZIF-8载体对Bi₂O₃的稳定支撑作用。且实验表明纯ZIF-8的禁带宽度大仅响应紫外光，在与Bi₂O₃复合后吸收带边红移，拓宽可见光响应范围，等效禁带宽度降低。

Abstract

In this study, ZIF-8 synthesized via the hydrothermal method was used as a carrier. Bi₂O₃ precursors were in-situ loaded, and artificial intelligence (AI) algorithms were introduced to fabricate Bi₂O₃/ZIF-8 composite photocatalysts. An integrated system of “AI-assisted synthesis – proportion prediction and analysis – optimization of degradation conditions” was established.AI assisted orthogonal experimental design was employed, with hydrothermal temperature (120~150 °C), reaction time (2~4 h) and theoretical Bi₂O₃ loading (10%~25%) as independent variables and degradation rate as the response value. A second order polynomial regression model was established, and the optimal parameters were determined to be 135 °C, 2.5 h and 18%. The relative error between model predicted and experimental values was less than 5%. Characterizations of phase structure and micromorphology reveal that ZIF-8 features a large specific surface area and outstanding porous framework, which effectively improves the dispersion of Bi₂O₃ nanoparticles and drastically enriches active sites of the composite, thereby endowing the material with enhanced photocatalytic activity. Experimental results demonstrate that the Bi₂O₃/ZIF-8 composite achieves optimal photocatalytic performance at a Bi₂O₃ loading content of 18%, with a tetracycline degradation efficiency of 81.9% for 10 mg/L tetracycline solution. Quenching experiments reveal that the contribution ratios of ·O₂⁻, h⁺ and ·OH to degradation are approximately 65%, 22% and 13%, respectively；Moreover, the degradation efficiency remains above 76.9% after five consecutive recycling tests, indicating excellent reusability of the catalyst, which is mainly attributed to the stable support effect of ZIF-8 matrix on Bi₂O₃ nanoparticles. Furthermore, experiments show that pure ZIF 8 has a large band gap and only responds to ultraviolet light. Upon compositing with Bi₂O₃, the absorption edge exhibits a red shift, the visible light response range is broadened, and the equivalent band gap energy decreases.