机械诱导合成氢钨青铜/碳量子点光催化降解性能

Photocatalytic Degradation Performance of Mechanically Induced Synthesized Hydrogen Tungsten Bronze/Carbon Quantum Dots

摘要

针对光催化体系对可见和近红外光利用效率低及光催化材料氢钨青铜制备中需高温、贵金属催化剂的问题，设计开发了一种便捷的机械化学合成技术，以塑料产品聚丙烯(PP)同时作为氢源和碳源，通过机械能诱导的氢溢流反应在常温下合成碳量子点复合的氢钨青铜．研究了氢钨青铜/碳量子点(H_xWO₃/CQDs)复合材料光催化降解抗生素类污染物盐酸四环素(TC)的性能．结果表明，三氧化钨(WO₃)与 PP 两者经由球磨法原位一步反应并复合．使用质量比为 48∶1 的 WO₃ 与 PP 粉末、球料比为 100∶1、总质量为 5 g 的混合材料在真空条件下进行高能球磨 3 h 得到的产物在近红外光区产生吸收．在 TC 质量浓度高达 20 mg/L 时模拟太阳光(300 W)下催化反应 1 h 的降解率仍可达 50%，催化性能相比于单独球磨的 WO₃ 提高了 35%，且在 pH 3～11 的范围内保持了该降解能力．模拟光辐射反应 4 h 后，将反应体系置于自然光环境下连续反应 44 h TC 的降解率达到近 90%．高能的物理球磨作用导致 PP 机械解聚，分解产生的氢溢流还原 WO₃，产生具有高度有序纳米结构的 H_xWO₃ 和副产物 CQDs．该原位还原和复合的合成方式促进了催化剂的光吸收及对污染物的吸附氧化，提供了简便快捷、条件温和、高产量的复合光催化材料一体化绿色制备技术，可促进塑料废弃物资源化利用和自然光催化技术在环境治理中的应用与发展．

Abstract

A convenient mechanochemical synthesis technology was designed and developed to address the low utilization efficiency of visible and near-infrared light in photocatalytic systems，as well as the reliance on high-temperature processes and precious metal catalysts in the preparation of hydrogen tungsten bronze photocatalytic materials. The plastic product polypropylene(PP)was used simultaneously as a hydrogen and carbon source，and a carbon quantum dots-hydrogen tungsten bronze composite was synthesized at room temperature through mechanically induced hydrogen overflow reaction. The photocatalytic degradation performance of the hydrogen tungsten bronze/carbon quantum dots(H_xWO₃/CQDs)composite toward the antibiotic pollutant tetracycline(TC)was investigated. The experimental results demonstrate that tungsten trioxide(WO₃)and PP undergo a one-step reaction and in situ compositing via ball milling. When WO₃ and PP powders with a mass ratio of 48∶1 were used，with a ball-to-material ratio of 100∶1 and a total mass of 5 g，the product obtained by high-energy ball milling under vacuum for 3 h exhibited absorption in the near-infrared region. At a TC mass concentration of 20 mg/L，the catalytic degradation rate under simulated sunlight (300 W)for 1 h reached 50%，which was 35% higher than that of ball-milled WO₃，and the degradation activity was maintained over a pH range of 3—11. After 4 h of simulated light irradiation，the degradation efficiency of TC reached nearly 90% when the reaction system was subsequently placed in a natural light environment and allowed to react continuously for 44 h. The high-energy ball-milling process induced mechanical depolymerization of PP，and the hydrogen generated during decomposition overflowed to reduce WO₃，forming H_xWO₃ with highly ordered nanostructures and by-product carbon quantum dots. This in situ reduction and composite synthesis strategy enhanced the catalyst’s light absorption and promoted pollutant adsorption and oxidation. The method provides a simple，rapid，mild-condition，and high-yield integrated green preparation technology for composite photocatalysts，facilitating the resource utilization of plastic waste and supporting the application and development of natural light-driven catalysis in environmental remediation.

关键词

机械诱导合成 / 碳量子点 / 钨青铜 / 光催化 / 四环素

Key words

mechanically induced synthesis / carbon quantum dots(CQDs) / tungsten bronze / photocatalysis / tetracycline(TC)

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基金资助

国家自然科学基金资助项目(22376107)

天津市自然科学基金资助项目(24JCYBJC01640)

南开大学沧州渤海新区绿色化工研究院基金资助项目(NCC2022-PY-01)