碳纳米管多层膜宏观体的CVD法制备、结构调控及海水淡化性能研究

Due to their unique tubular structure, exellent mechanical property, electrical property, and structural stability, carbon nanotubes (CNTs) are expected to have a wide range applications by replacing the currently used traditional materials. To fufil specific requirements, CNT macroscopic structures are often reqiured. The commonly used methods for obtaining macroscopic CNT membranes usually involve a series of physical and chemical treatment processes and hence inevitably introduce structural defects into CNTs and deteriorate their performance. In this application, we propose to prepare CNT multi-layer membrane macroscopic structure directly by using a floating catalyst CVD method. By tuning the hydrocarbon concentration, catalyst concentration, growth temperature, amount of growth promoter used, and deposition time, the porosity, pore distribition, and thickness of the CNT membranes can be controlled. The forming law and mechanism of the CNT multi-layer membranes will be studied both experimentally and theoretically. The obtained hydrophobic CNT membranes will be used for see water purification by direct contact membrane distillation. The effect of the porosity, pore distribution and surface state on the desalination efficiency and operating lifespan of the CNT membranes will be investigated. Then, the structure and preparation parameters of the CNT multi-layer membrane macroscopic structure will be optimized. The objective of this project is to clarify the forming law and structure control mechanism of the CNT multi-layer membranes, and to explore the feasibility of their applications for sea water desalination.

碳纳米管具有独特的中空管状结构、优异的力学电学性能和良好的结构稳定性，可望在诸多领域替代传统材料获得应用。为满足特定的应用需求，往往需要将碳纳米管组装成宏观体结构。常用的制备碳纳米管膜宏观体的先分散再后处理方法因涉及一系列物理、化学过程，不可避免地会在碳纳米管中引入结构缺陷并影响其性能发挥。本申请提出采用浮动催化剂CVD法直接制备碳纳米管多层膜宏观体。通过控制碳源浓度、浮动催化剂浓度、生长温度、生长促进剂加入量和沉积时间等，调控碳纳米管多层膜的孔隙率、孔径分布、厚度等结构特征。实验与计算模拟相结合，研究碳纳米管多层膜的生成规律与机制。将所得疏水性碳纳米管多层膜用于直接接触式膜蒸馏海水淡化，考察多层膜的孔隙率、孔径分布、表面状态等对其脱盐效率和稳定性的影响；优化碳纳米管多层膜的结构和制备方法。本项目旨在阐释碳纳米管多层膜宏观体的生成规律及结构控制原理，为其在海水淡化等方面的应用提供科学依据。

碳纳米管具有独特的中空管状结构、优异的力学电学性能和良好的结构稳定性，可望在诸多领域替 代传统材料获得应用。为满足特定的应用需求，往往需要将碳纳米管组装成宏观体结构。常用的制备 碳纳米管膜宏观体的先分散再后处理方法因涉及一系列物理、化学过程，不可避免地会在碳纳米管中 引入结构缺陷并影响其性能发挥。本申请提出采用浮动催化剂 CVD 法直接制备碳纳米管多层膜宏观 体。通过控制碳源浓度、浮动催化剂浓度、生长温度、生长促进剂加入量和沉积时间等，调控碳纳米 管多层膜的孔隙率、孔径分布、厚度等结构特征。实验与计算模拟相结合，研究碳纳米管多层膜的生 成规律与机制。将所得疏水性碳纳米管多层膜用于直接接触式膜蒸馏海水淡化，考察多层膜的孔隙 率、孔径分布、表面状态等对其脱盐效率和稳定性的影响；优化碳纳米管多层膜的结构和制备方法。 本项目旨在阐释碳纳米管多层膜宏观体的生成规律及结构控制原理，为其在海水淡化等方面的应用提 供科学依据。