常压反应性等离子体多场耦合沉积TiO2片晶三维结构薄膜动力学

3D nanosheets-connected films designed appropriately with two exposed high active facets are highly desirable for crystal surface research and technical applications in the fields of new energy, new materials and environment etc.. Based on the original experimental results obtaining 3D anatase TiO2 micro/nanosheet-connected films with two large exposed {001} facets, this project aims to further investigate the deposition kinetics to get such film through TiCl4/O2/Ar reactive atmospheric plasma. Through experimental and numerical simulation, we will study the plasma discharge characteristics and stability and explore the elementary physical and chemical reaction and main path, as well as the energy and/or density of the main active species. We will also investigate their gathering and nucleating process in the gas phase and the nucleating, crystallizing and architecture evolution on the substrate in real-time. The kinetic mechanism will be also discussed. The structure, photocatalysis, photoluminescence and their relationship will be also found out for this 3D anatase TiO2 nanosheet-connected films with two large exposed high energy facets. More importantly, the influence of the plasma factors coupled with the active species density, plasma electric field and temperature distribution on the composition, structure and property of the film will be explored, gaining understanding the mechanism of the self-refined growth and connection of the crystal sheets with high energy facets in this highly reactive plasma. Above work will develop a controllable new fabrication method to deposit 3D nanosheet-connected films with two large exposed active facets and with novel properties, enriching the theory of the atmospheric plasma chemical vapor deposition and meeting with the great demand in new energy and environmental applications for fast , low cost and environmental-friendly film fabrication way.

片晶三维结构金属氧化物半导体薄膜在新能源、新材料、环境等领域具有重要应用价值。本项目拟在沉积具有大比例高能活性面锐钛TiO2片晶三维结构薄膜原创性结果的基础上，深入研究常压反应性等离子体多场耦合薄膜沉积动力学。通过实验和数值模拟，研究TiCl4/O2/Ar等离子体放电特性及稳定性，实时探索气相主要物理化学反应及其路径，主要活性粒子的能量、密度及聚集或成核演变过程，表面相成核、结晶、形貌演变的过程与机理；深入研究TiO2片晶三维结构薄膜结构形貌、光催化活性、荧光特性及相互关系；探索等离子体多场耦合作用参数如活性粒子特性、等离子体电场与外加温度场等对高能活性面生长及晶片连接、薄膜结构特性的影响及关键控制因素。丰富和发展常压反应性等离子体薄膜沉积理论和可控制备方法，为具有新颖结构特性的金属氧化物半导体片晶三维微纳米结构薄膜的可控制备提供一个新途径，满足能源环境等领域对低成本快速高效成膜方法的需求

通过常压反应性等离子体薄膜沉积及气相及表面相反应动力学过程的模拟和实验研究，探索了TiCl4/Ar/O2常压反应性等离子体多场耦合沉积TiO2片晶三维结构薄膜的机理和规律。模拟结果显示，TiO2的生成路径主要是通过TiO2Cl3电子解吸附反应生成TiO2Cl2，随后通过和电子的系列反应分别生成TiO2Cl和10 nm左右的纳米颗粒；通过脉冲调制等离子体射频放电和激光散射光谱，率先直接动态观察到了高电负性颗粒被射频鞘束缚在鞘边缘以及脉冲关时的“库伦爆炸”现象，以及随脉冲调制在等离子体相及表面相成核、结晶、形貌演变的物理化学过程与机理；结合气相成分的调控及OES实验诊断，研究了不同反应阶段表面相颗粒聚集、成核、单晶片连接生长的演变发展过程，认为大比例（001）高活性面暴露的TiO2纳米片晶三维结构薄膜形成的机理是由于高电负性体系对（001）高活性面钝化及自限制生长作用，实现了三维结构薄膜在整个辉光放电区域的可控制备。实验探索了脉冲调制射频放电等离子体的特性与放电稳定性，在较低的放电电压下获得稳定辉光放电，并通过双射频电源同时加载的形式，率先实现了较高密度、较高活性及低气体温度的常压双频He辉光等离子体。同时，研究了等离子体频率、外加温度场等多场耦合作用参数对薄膜结构特性和空间均匀性的影响，通过频率下降和结合基片温度变化，获得了大尺度均匀的、黏附力与结晶良好的纳米颗粒沉积薄膜和三维结构薄膜。同时通过He/H2等离子体体系对二氧化钛薄膜的H掺杂与VOs自掺杂作用，在极短时间内制备了黑色TiO2薄膜。.薄膜结构特性的研究结果表明，白色锐钛矿TiO2片晶三维微纳米结构薄膜具有很强荧光及对金黄色葡萄球菌的光催化灭菌特性，荧光特性与光催化灭菌特性分别与自掺杂OVs和大比例暴露的高活性（001）面相关；黑色TiO2颗粒膜在可见和红外波段具有较高的吸收特性，以及较好的可见光电流响应特性，对甲基橙和亚甲基兰的可见光催化降解率与对照样相比有较大幅度提高。.通过动力学模拟和实验研究，阐明了具有独特结构和性能的三维锐钛矿二氧化钛纳米结构薄膜的成形机理。常压反应性等离子体沉积和表面处理可以快速在线完成卷对卷制备过程，扩展了常压反应性等离子体薄膜沉积和表面处理的实验与理论研究，具有很好的应用前景。