专栏名称: AEii国际应用能源
发布应用能源领域资讯,介绍国际应用能源创新研究院工作,推广应用能源优秀项目,增进应用能源领域合作
目录
相关文章推荐
中国舞台美术学会  ·  宋晨:小角色,科技浪潮大舞台——评歌剧《横琴依依》 ·  2 天前  
中国舞台美术学会  ·  通知丨最高10万补贴速领,2025国家文旅科 ... ·  2 天前  
中国舞台美术学会  ·  《舞台上下六十秋》:书就六十载话剧人生与戏剧情缘 ·  4 天前  
中国舞台美术学会  ·  资讯丨国家五部门联合发文:优化消费环境,鼓励 ... ·  3 天前  
51好读  ›  专栏  ›  AEii国际应用能源

【Applied Energy最新原创论文】基于低共熔溶剂解离纳米木质素的碳基分级孔超级电容电极材料制备与性能研究

AEii国际应用能源  · 公众号  ·  · 2024-02-04 13:32

正文

原文信息:

Production of hierarchical porous bio‑carbon based on deep eutectic solvent fractionated lignin nanoparticles for high-performance supercapacitor

原文链接:

https://www.sciencedirect.com/science/article/abs/pii/S0306261923014599

Highlights

(1) 氯化胆碱:乳酸型低共熔溶剂可从生物质中解离出超60%的木质素

(2) 低共熔溶剂解离获得的木质素呈粒径均一的纳米分散态

(3) 未回收的小粒径(<10 nm)木质素溶解于低共熔溶剂中并表现出荧光性

(4) 一步活化解离木质素可以产生微孔-介孔分级孔结构(比表面积高达3577 m 2 g -1

(5) 解离木质素活化后的比电容在0.5 A g -1 电流下可高达248.8 F g -1

摘要

低共熔溶剂(DES)由于较低的合成成本、较低的生物毒性和较优秀的木质素溶解能力,近年来被应用于解离木质纤维素有机组分的研究中。作为DES解离的主要产物之一,解离木质素的利用常常被忽视,造成了资源浪费。本文利用氯化胆碱:乳酸型低共熔溶剂从小麦秸秆中解离出高分散的纳米木质素颗粒。该解离木质素被应用于制备碳基超级电容器中,并表现出比传统木质素基超级电容更高的比容量。结果表明,在低温下延长解离时间可显著促进木质素从生物质中的脱除过程,但在高温下DES与生物质的比例将成为木质素溶解的速率限制条件。DES解离可获得木质素纳米簇,且提高解离温度有利于木质素纳米簇的形成。DES解离过程中,木质素-碳水化合物复合物以及木质素基本单元的断裂是形成该纳米簇的关键。同时,木质素纳米颗粒会在长时间的解离中发生团聚。一步法活化可在较短解离时间的木质素中产生分级孔结构(微孔+介孔),而团聚程度更严重的解离木质素需要两步法进行活化。DES解离木质素在活化后比表最高可达3577.3 m 2 g -1 ,以此为基底制备的碳基超级电容的比电容可达248.8 F g -1 。该研究提供了一种利用DES解离从木质纤维素生物质中获得纳米木质素并用于制备高性能碳基电化学储能材料的新方法。

更多关于"supercapacitor"的研究详见:

https://www.sciencedirect.com/search?qs=supercapacitor&pub=Applied%20Energy&cid=271429

Abstr act

Owing to the low synthetic cost, low toxicity for most types and outstanding lignin solubility, deep eutectic solvents (DESs) have been recently exploited in fractionation of lignocellulosic biomass. Unfortunately, the DES-fractionated lignin, as another major product, was usually ignored and disposed improperly. Accordingly, the present study employed DES (choline chloride:lactic acid) to fractionate natural biomass for producing highly dispersed lignin nanoparticles. The obtained nano-lignin was utilized to prepare electrode materials for supercapacitors for the first time, and a higher specific capacitance than those prepared from conventional lignin was acquired. The results demonstrated that the lignin fractionation rate could be promoted via extending treatment time at low temperatures, whereas the DES to biomass mass ratio might be the lignin dissolution-limiting factor at high temperature. Uniform lignin nanoclusters could be obtained after DES fractionation, and increasing fractionation temperature was beneficial for preparing nano-lignin in DES. The cleavages of lignin-carbohydrate complexes and lignin subunits might account for the formation mechanism of lignin oligomers. Meanwhile, the aggregation of monolignols could contribute to the growth of lignin nanoparticles. The one-step KOH activation could induce hierarchical pores in lignin fractionated from moderate residence time, whereas two-step method was advisable for more aggregated DES-lignin. Based on the directly activated DES-lignin with a high surface area of 3577.3 m 2 g -1 , the prepared supercapacitor exhibited a superior specific capacitance of 248.8 F g -1 . This study aimed to provide a novel method for producing high-performance energy storage carbon materials based on DES fractionated lignin from lignocellulose.

Graphics

图1 生物质低共熔溶剂解离及解离木质素制备分级孔碳材料示意图

图2 小麦秸秆在氯化胆碱:乳酸体系中的木质素脱除率(上),解离木质素形貌(中),未回收木质素的荧光特性(下)

图3 不同活化方式对解离木质素基碳材料孔径分布的影响

图4 解离木质素基超级电容的循环伏安曲线(左)与恒流充放电性能(右)







请到「今天看啥」查看全文