宽光谱“铌”基材料构筑及其在环境净化中应用

The development of novel highly efficient visible-light photocatalysts and their applications on environmental purification of emerging contaminats and energy saving, have attracted much attention. This research describes preparation of bismuth niobate with orthorhombic phase and triclinic phase by soft chemistry approach (such as sol-gel, co-precipitation, hydrothermal and microwave hydrothermal). Comparing the two phase’s photocatalytic activity, the higher activity phase is selected. Based on the up-conversion properties of carbon quantum dots, bismuth niobate were used to fabricate broad spectral niobate-based photocatalysts. The preparation methodology, the extent of the distribution of nanoparticles and the composition at various ratios may influence the structure and catalytic acitivity will be evaluated by modern materials characterization technology. And thus the binding mechanism will be identified. The catalytic performance of bismuth niobate may be regulated. Potential applications in environmental purification of the prepared niobate-based photocatalysts have also been studied. The photocatalytic activities of the composites were systematically investigated on the degradation of quinolones drugs. The factors which influenced the catalytic performance, the dynamic equations and the degradation mechanisms of quinolones drugs were studied. The preparation of this novel catalyst will be of great significance to further development other material. It has important academic significance on promoting environment, chemical industry, energy and materials industry interdisciplinary integration.

研究和开发新型高效可见光催化材料用于去除环境中新兴有机污染物，对解决环境污染和能源短缺等问题具有重要科学意义和实用价值。本项目拟采用软化学方法（如溶胶-凝胶、共沉淀、水热和微波水热等）制备出正交相和三斜相铌酸铋纳米材料，通过两相催化活性筛选，优选出高活性铌酸铋相。选择具有上转换特性的碳量子点，与铌酸铋复合，构筑宽光谱“铌”基材料。利用现代材料表征技术，深入分析制备方法、表面状态和组成变化对该类复合材料结构和催化活性之间的调变作用，确定调变机理，从而实现对铌酸铋催化性能的有效调控。为了进一步拓展宽光谱“铌”基材料在环境净化方面的应用，将复合材料用于环境中新兴污染物喹诺酮类抗菌药可见光催化降解，系统研究影响催化性能的因素，建立降解动力学方程，揭示喹诺酮类抗菌药催化降解机理。本项目不仅为开发新型环境净化材料提供了一条途径，也促进了环境、化工、能源和材料等多学科交叉融合，具有十分重要的学术意义。

研究和开发新型“铌”基材料用于去除喹诺酮类抗生素残留，对解决环境污染和能源短缺等问题具有重要科学意义和实用价值。本项目首先通过水热法成功合成了具有优良光催化活性的亚稳态铌酸铋纳米材料，将此材料进一步高温煅烧，通过反应温度的调控成功制备出了正交晶型和三斜晶型的铌酸铋纳米材料，发现正交晶型的光催化性能优于三斜晶型。采用水热法合成了碳量子点，利用碳量子点的特殊性质，将其与铌酸铋材料复合，制备成宽光谱“铌”基材料，以喹诺酮类抗生素沙拉沙星为降解对象，评价了碳量子点/铌酸铋复合材料光催化性能，在光催化降解沙拉沙星的过程中产生了4个新的降解中间产物。其次，本项目采用溶剂热法制备了铌酸铟材料，发现不同温度和pH条件下合成的铌酸铟材料形貌和性能差异较大，最优条件下合成的铌酸铟材料为立方体形貌，该样品具有较高的光响应强度、较大的比表面积和较优的光催化性能，可用于喹诺酮类抗生素培氟沙星的去除，研究发现了培氟沙星5个降解产物，超氧自由基和空穴是降解过程中产生的主要活性物种。除此之外，本项目还采用水热法合成了新型铌酸锡材料，以喹诺酮类抗生素达氟沙星为去除目标，研究了铌酸锡吸附剂的吸附性能和吸附机理，发现了吸附剂用量、吸附温度、pH值及吸附时间等对吸附效率均能产生影响。本项目所开发的“铌”基材料，具有光谱响应范围宽，催化活性高，可调控性好等优点，可有效去除环境中喹诺酮类药物沙拉沙星、培氟沙星和达氟沙星的残留，喹诺酮类药物的光催化降解过程中涉及到哌嗪环的开环和氧化等分子机制。本项目不仅为开发新型环境净化材料提供了一条途径，也促进了环境、化工、能源和材料等多学科交叉融合，具有十分重要的科学意义。