铜盐辅助木质素基碳气凝胶的快速制备及其电化学性能研究

Study on Copper Salt Assisted Fast Preparation of Lignin-based Carbon Aerogel and Its Electrochemical Properties

中文关键词:  纳米木质素  碳气凝胶  催化  电化学

Key Words:lignin nanoparticles  carbon aerogel  catalysis  electrochemical

中文摘要:

      本研究提出了一种铜盐辅助纳米木质素基气凝胶的快速合成方法，实现了具有显著微孔特征和三维（3D）互联结构的碳气凝胶制备。以绿色低共熔溶剂（DES）为反应溶剂，原位添加铜盐催化剂，快速合成了纳米木质素基碳气凝胶前驱体（LRF），经过高温一步热解处理得到木质素基碳气凝胶（LRFC）。研究结果表明，铜盐的原位掺杂加快了胶体形成的反应速率，缩短了LRF的成胶时间。其中，Cu（NO₃）₂的原位催化效果最好，可使得LRF凝胶点缩短至2.5 h；同时，其相应的碳气凝胶（N-LRFC）的微孔率高达94.44%，孔径集中分布在1 nm；在电流密度为0.5 A/g时，N-LRFC的比电容最高可达347.6 F/g，表现出优异的电化学性能，且在电化学过程中其扩散控制占主导地位。

Abstract:

      A fast synthesis method of lignin nanoparticles （LNP）-based aerogel was proposed to prepare three-dimensional （3D） interconnected carbon aerogel with a typical micropores structure. Green and low-cost deep eutectic solvent （DES） used as the reaction solvent， three copper salts added in-situ as the catalyst， and LNP-based cryogel（LRF） as a precursor can be rapidly synthesized for lignin-based carbon aerogel （LRFC）. The study results showed that in-situ doped copper salt can accelerate the gelation rate of gel formation and decrease the gelation time of LRF. Herein， the gel formation of Cu（NO₃）₂ assisted LRF can be shortened to 2.5 h， and the resultant carbon aerogel （N-LRFC） had the highest microporous rate of 94.44% and pore size of 1 nm， high graphitization， and excellent electrochemical performances. At current density of 0.5 A/g， N-LRFC demonstrated exceptional electrochemical performance with a specific capacitance of up to 347.6 F/g. and the diffusion control dominated the electrochemical process.