木质素表面修饰和配位策略构筑炭基催化剂及微纳结构调控机制

The high-value carbonization of lignin from forestry resources to prepare carbon based functional catalysts has significant environmental and economic benefits. The composition and coordination state of carbon source play an important role in the structure design and function control of the catalyst. However, the compositional singleness and invariability of traditional fossil-based carbon sources, such as benzene and acetylene, constrain the composition and morphology uncontrollable of the derived catalysts. This project intends to use the lignin, which is easily modified by the surface structure, as the carbon source and to build a metal-lignin coordination system. Through surface modifying and regulating the coordination states of lignin and metal ions, we can prepare carbon coated transition metal catalysts by regulating the chain length of chain-like carbon source and by optimizing the carbonization process to control the stepwise carbonization of chain-like carbons and aromatic carbons. Thereby, the particle size, dispersity, graphite layer thickness, and coating method can be precisely controlled. Based on systematic experiments and theoretical computation, we could clarify the relationship between ligand design, preparation conditions, and micro-nanostructural regulation, propose a strategy for fine carbonization and resource utilization of metal-lignin complexes, and provide a general scheme for the high utilization of lignin and the design of adjustable carbon based catalysts.

低值林业资源木质素高值炭化制备炭基功能催化剂具有重要的环境和经济效益。碳源的构成和配位状态是催化剂结构设计和功能调控的关键，但苯、乙炔、甲烷等传统化石碳源结构单一固定，导致其衍生催化剂的组成与形态难以调控。本项目提出以分子结构易于优化的木质素为碳源，采用表面修饰的方法引入配位中心，构建金属-木质素配合物体系，进而通过调控二级链状碳源的链长并优化炭化工艺控制链状碳和芳香碳分步炭化，最终构筑微纳结构可调的炭包裹过渡金属催化剂，实现其颗粒尺寸、分散性、石墨层厚度以及包裹形式的精确控制。本项目将在实验结果和理论计算的基础上，阐明木质素源配体设计-制备条件-微结构调控三者之间的关系，提出一种金属-木质素配合物精细炭化资源化利用的普适性策略，为木质素的高值化利用和结构可调的炭基催化剂的设计提供通用依据。

木质素是一种非结晶性的、三维网状酚类天然高分子生物质，在天然木材成分中其含量仅次于纤维素和甲壳素，开发利用木质素替代石化原料制备炭基功能催化剂具有重要的环境和经济效益。经过三年的系统探索，我们取得的主要亮点包括：1）建立了木质素源配体的合成方法，解析了配体的种类、数量和位置对金属-木质素配合物空间结构的影响规律，获得了一种金属-木质素配合物微纳结构精细调控资源化利用的普适性策略；2）以金属-木质素配合物为前驱体，获得了形态可控的TM@GC催化剂通用制备方法，揭示了配体性质和炭化工艺对TM@GC催化剂形态调控的影响机制；3）明确了木质素源前驱体设计合成-制备条件-形态调控三者之间的关系，阐明了金属-木质素配位机制对制备形态可调的TM@GC催化剂的独特作用。为解决制备炭材料过度依赖化石资源和农林废弃物清洁高效利用等问题提供了重要技术方法和理论指导。共发表论文13篇，其中SCI收录12篇；申请国家发明专利9件，已授权7件；参加学术会议3次，培养硕士研究生3名；入选江苏省“青蓝工程”优秀骨干教师，荣获中国商业联合会科技进步一等奖（1/9）、江苏省职工十大科技创新成果奖和常州市自然科学优秀科技论文二等奖等奖励5项。