新结构高性能多尺度复合炭素材料的设计、合成及其海水淡化性能研究

The consumption and sustainable supply of fresh water have become one of the top priority issues faced by the global community. Recently, the capacitive deionization (CDI) technology for desalination has drawn much attention because of its potential as an environmentally-friendly yet energy-efficient alternative to membrane desalination and thermal processes currently available for producing fresh water from salted water sources. For the CDI technology, the electrode materials with tuned pore structure and surface properties and functions such as conductivity are the key to an efficient desalination process. This project aims to deliver techniques that can greatly improve the adsorptive capacity and the ion selectivity of the carbon electrodes used in CDI processes. For this project, the main issues to be addressed include, but not limited to: to develop new strategies for fabricating novel hierarchical functional carbon materials with tuned structure and properties for CDI; to develop techniques for tuning the pore structures and surface properties of the concerned carbon materials as electrosorptive electrodes; to study the interaction of the ions with pore surface and interfaces in the carbon electrodes and to understand the transport mechanism in the pore structures; to develop and establish strategies for the design and large scale fabrication of the carbon electrodes with different yet tuned forms and textures in general, and with greatly improved long-life reusable performance for CDI in particular; to develop new principles and methods that will pave a new way for making competitive low-operation-cost CDI processes to solve the bottle-neck problems faced by the desalination of salted water resources. These efforts will give an impetus to the development of the CDI technologies not only in China but also in the world.

电容去离子技术是一种低耗高效环保的苦咸水脱盐高新技术，其核心和关键是高性能炭基电极材料的创制。本项目针对目前炭材料电极脱盐容量低、离子吸附选择性差等瓶颈性难题，研究并建立创制结构新颖、性能优异的炭电极材料的新技术策略，提出并发展调控炭电极材料的孔道结构及其表面物理化学性质的新方法，研究揭示金属离子与炭电极表面/界面的相互作用机制、及其在炭材料多级孔道结构中的输运特性；提出并建立功能性炭电极材料的新设计理念和调变策略，解决传统的电容去离子脱盐电极材料抗污染能力弱、循环使用性能差等关键问题，研究建立规模化构筑新型功能化炭电极材料和电容去离子模块化组装结构的新技术方法，发展基于电容去离子技术的低耗、无污染、高效苦咸水脱盐及污水脱盐回用再生的新原理和新方法。项目的实施将为开发低耗高效环境友好的苦咸水/海水淡化、污水再生及生物质化学品脱盐等技术奠定理论和技术基础，有重要的学术价值和广阔的应用前景。

电容去离子技术是一种低耗高效环保的苦咸水脱盐高新技术，其核心和关键是高性能炭基电极材料的创制。本项目针对目前炭材料电极脱盐容量低、循环稳定性差等瓶颈性难题，开展系列工作。采用静电纺丝技术，研究并建立创制结构新颖、性能优异的碳纤维复合电极材料的新技术策略；提出并发展氧化、氨基化及磺化反应调控炭电极材料的表面物理化学性质的新科学方法，研究揭示了金属离子与炭电极表面/界面的相互作用机制；提出并组装无离子交换膜的杂化电容去离子模块新设计理念和调变策略，以此提高脱盐量（14.9 mg g-1）及电流效率（60 %）；研究并建立了油水分离用碳纳米管/石墨烯复合材料的新技术思路；研究并发展了重金属脱除方面有良好效果的ZIF-8/碳纤维复合材料及改性聚丙烯腈凝胶材料合成新技术；研究建立规模化构筑新型功能化炭电极材料和电容去离子模块化组装结构的新技术方法，该系统的吨水处理能耗为1.15 kWh；绿色能源太阳能电池用于CDI的输出，实现了55 %以上的能量回收率，进一步降低了CDI技术的能耗。成果为开发低碳、低耗、低廉及低污的苦咸水/海水淡化、污水再生及生物质化学品脱盐等技术奠定了理论和技术基础，有重要学术价值和广阔应用前景。