基于介孔/微孔分层次组合的纳米阵列多孔碳材料微结构设计与调控及超级电容特性研究

The carbide-derived carbon (CDC) is a new class of nanostructured porous carbon materials with 3D ordered structure and precisely tuning pore size. Due to the irregular curved pore connection, slow electrolyte ion transport rate and low energy density of CDC, this project will prepare the new nano-array hierarchically ordered CDC with combination of mesopore/micropore, ultrahigh specific capacitance, excellent frequency response, and capacity retention at high current densities. The new CDC are obtained by first preparing ordered mesoporous chromium carbide precursor by SBA-15 and nanocasting,followed by selective extraction of chromium through chlorination reaction. Thermodynamic modelling is built to estimate the effect of various process parameters on CDC formation and the selection of the optimum synthesis conditions by Factage 5.3 (GTT technologies, Germany). The kinetic rule of chlorination reaction was studied to precisely design and control mesopore/micropore structure. At the same time, the relationship of electrolyte ion size, porous structure in CDC and ion transport rate will be discussed, and correlation of pore size, ion transport rate and specific capactiance will studied systemically. Based on the quantitative research on mespore/micropore structure and storage characteristics of supercapacitor, the formation mechanism , change rule and controlling technology of the mesopore/micropore in nano-array hierarchically ordered CDC will be ascertained, and the electrochemical storage energy mechanism of novel CDC with quick ion transport rate will be explained. Above works will provide experimental support and theoretical guidance for the development of ultrahigh specific energy supercapacitor and new porous carbon.

碳化物骨架碳材料(CDC)是近年来发展起来的、具有三维有序结构、孔径精确可控的纳米级多孔碳材料。针对CDC存在孔形状不规则、离子传输速度慢和储能特性有待提高等问题，提出用SBA-15模板和纳米注入技术制备纳米阵列碳化铬前驱体，原位氯化反应制备具有纳米阵列有序排列、介孔/微孔分层次组合、高电流密度下有高比电容、优良功率特性、频响特性和容量保持率的局域石墨化新型CDC。用Factage5.3建立氯化反应热力学模型，并探讨氯化反应动力学规律，在纳米尺度上设计和调控介孔/微孔结构，明晰电解质离子半径、CDC孔结构与离子传输速率的定量关系，探索孔径、离子传输速率与比电容的耦合规律。通过对介孔/微孔结构与超级电容器储能特性的定量研究，确定有序纳米阵列多孔碳微结构的形成、演化规律及控制方法，揭示具有离子快速传输能力的新型CDC的电化学储能机理，为高比能超级电容器和多孔碳材料的发展提供实验依据和理论指导。

超级电容器作为一种新型储能器件，兼有电池高比能量和传统电容器高比功率的特点，成为化学电源领域新的产业亮点。目前应用最为广泛的是碳基超级电容器(EDLC)。EDLC的性能在很大程度上取决于碳材料的性质，常用的多孔碳材料有活性炭、碳气凝胶、碳化物骨架炭(CDCs)等。其中CDCs作为一种新型的多孔碳材料，它具有高的比表面积、孔径大小和孔径分布精确可调，因此成为较为理想的超级电容器电极材料。本项目在对CDC结构设计、制备、性能表征和多孔碳材料分级孔组合、SBA-15模板法制备功能性多孔炭材料等前期研究工作的基础上，发展了一种具有高能量密度和离子快速传输能力的CDC制备新路线，制备出具有介孔/微孔分级孔组合、孔径可根据电解质离子尺寸设计并调控、电化学性能优良的超级电容器新型电极材料。同时从理论上确定了材料结构、性能的定量关系，运用现代电化学研究和材料结构分析、表征手段研究新型CDC的电化学规律，解决制约高性能超级电容器发展的关键问题。不但可以促进高性能超级电容器和电动车产业的发展，而且可在新型多孔炭材料的制备、结构表征和性能的定量研究方面做出重要创新，为其在储能、气体储存和催化剂等领域的应用提供方法指导和科学依据。