基于氧化锌纳米线的平面微流体反应器光催化性能研究

The photocatalytic technology has been extensively studied during the past decades and it exhibits great application potential in decomposing the pollutants in aqueous solution. However, nanostructured photocatalyst as the core of the photocatalytic technology is difficult to be integrated into devices, which hinders the development of photocatalysis heavily. In this project, we would develop a novel and high-efficiency immobilized photocatalytic reactor by fabricating a planar microfluidic reactor with ZnO nanowires as the photocatalyst. The planar microfluidic reactor is obtained by extending the active area of traditional microfluidic reactor in horizontal direction while large-area and uniform ZnO nanowires fabricated on the active area are utilized as immobilized catalyst. Firstly we will build the mass-flow model of the planar microfluid flow based on the microfluidic dynamics theory, to optimize the structural design of the photocatalytic reactor, to improve the integrated fabrication process, and to experimentally investigate the effect of the planar microfluid flow and device structures on the photocatalytic performance. Then we will improve the hydrothermal method to adjust the characteristic morphology of ZnO nanowires, and to investigate the effect of ZnO nanowire morphology on the photocatalytic performance. For further improving the photocatalytic activity and stability of ZnO catalysts, surface modification methods based on ZnO nanowires will be explored. In conclusion, through researching on the ZnO-nanowire-based planar microfluidic reactor, we aim to effectively integrate the microfluidic technology, nanotechnology and micro/nano fabrication technology with the photocatalytic technology in order to develop an efficient and effective photocatalytic reactor, providing technical support and theoretical guidance for the large-scale practical application of photocatalytic technology.

光催化技术在降解水中污染物方面具有广阔的应用前景，然而，光催化剂作为光催化技术的核心，其器件化问题一直是制约光催化技术发展的瓶颈。本项目拟开发一种新型高效的负载型光催化反应器，以基于氧化锌纳米线的平面微流体反应器为研究对象，从微观角度研究平面微流体的质量流动规律，建立反应器内部平面微流体的质量流动模型，探寻平面微流体质量流动及反应器结构设计对光催化性能的影响机理，从而优化反应器的结构设计与器件集成加工工艺；改进水热法合成氧化锌纳米线工艺，系统地研究纳米线特征形貌对光催化性能的影响规律，实现氧化锌纳米线特征形貌的择优调控，在此基础上，研究改进氧化锌纳米线表面复合修饰改性工艺，同时提高氧化锌材料的光催化活性与稳定性，开发高性能的负载型光催化剂。本项目旨在实现微流体技术、纳米技术、微纳加工技术与光催化技术的高效集成，研制高性能的光催化反应器，为光催化技术的大规模工业化应用提供理论指导和技术支持。

光催化降解水中污染物技术在水处理领域一直占有十分重要的地位。近年来，国内外研究学者在合成和改性光催化剂、开发新型光催化反应器等方面开展了大量卓有成效的研究工作。然而，对于负载型光催化反应器而言，催化剂与反应器之间的高效集成一直是人们研究的热点与难点。本项目将微流体技术与微纳米技术有效结合，以开发一种新型高效的负载型光催化反应器为目标，以基于氧化锌纳米材料的平面微流体反应器为研究对象，开展了平面微流体反应器光催化性能、氧化锌纳米材料制备工艺、氧化锌纳米材料修饰改性三个方面的研究工作。深入研究了关键工艺条件对氧化锌纳米线形貌的影响规律，掌握了氧化锌纳米线形貌调控方法；基于微流控芯片，实验研究了氧化锌纳米线在微通道中的可控合成，研究了生长液流速、生长时间等因素对微通道中氧化锌纳米线形貌的影响规律；研究制备了基于氧化锌纳米线的平面微流体反应器，并实验研究了器件的光催化性能；采用液相沉积法在氧化锌纳米线表面制备氧化钛纳米薄膜，研究了氧化钛纳米薄膜对氧化锌纳米线光催化性能的强化作用；采用水热法合成有纳米银颗粒表面修饰的氧化锌纳米结构，研究了纳米银颗粒对氧化锌纳米结构光催化性能的增强效果。本项目研究涉及微流体技术、纳米技术、微纳加工技术、光催化技术等多个领域，研究成果可为研制高性能负载型光催化反应器和光催化剂提供有益的借鉴，且可为光催化技术的大规模工业化应用提供一定的理论指导与技术支持。