Controlling the conductivity and microporosity of biocarbon to produce supercapacitors with battery-level energies at an ultrahigh power  

超高功率及电池级能量超级电容器用生物炭的导电性和微孔率调控

作　　者：CHENG Bei XIE Xing-yan WAN Liu CHEN Jian ZHANG Yan DU Cheng GUO Xue-feng XIE Ming-jiang 程贝;谢星艳;万柳;陈建;张燕;杜成;郭学锋;解明江(黄冈师范学院催化材料制备及应用湖北省重点实验室,湖北黄冈438000;南京大学介观化学教育部重点实验室,江苏南京210023)

机构地区：[1]Hubei Key Laboratory for Processing and Application of Catalytic Materials,Huanggang Normal University,Huanggang 438000,China [2]Key Lab of Mesoscopic Chemistry MOE,School of Chemistry&Chemical Engineering,Nanjing University,Nanjing 210023,China

出　　处：《新型炭材料(中英文)》2025年第2期409-420,共12页New Carbon Materials

基　　金：湖北省高等学校优秀中青年科技创新团队计划项目(T2020021),湖北省自然科学基金杰出青年基金项目(2024AFA086).

摘　　要：In order to meet the demands of new-generation electric vehicles that require high power output(over 15 kW/kg),it is crucial to increase the energy density of car-bon-based supercapacitors to a level comparable to that of batteries,while maintaining a high power density.We re-port a porous carbon material produced by immersing pop-lar wood(PW)sawdust in a solution of KOH and graphene oxide(GO),followed by carbonization.The resulting mater-ial has exceptional properties as an electrode for high-en-ergy supercapacitors.Compared to the material prepared by the direct carbonization of PW,its electrical conductivity was in-creased from 0.36 to 26.3 S/cm.Because of this and a high microporosity of over 80%,which provides fast electron channels and a large ion storage surface,when used as the electrodes for a symmetric supercapacitor,it gave a high energy density of 27.9 Wh/kg@0.95 kW/kg in an aqueous electrolyte of 1.0 mol/L Na_(2)SO_(4).The device also had battery-level energy storage with maximum energy densities of 73.9 Wh/kg@2.0 kW/kg and 67.6 Wh/kg@40 kW/kg,an ultrahigh power density,in an organic electrolyte of 1.0 mol/L TEABF4/AN.These values are comparable to those of 30−45 Wh/kg for Pb-acid batteries and 30−55 Wh/kg for aqueous lithium batteries.This work indicates a way to prepare carbon materials that can be used in supercapacit-ors with ultrahigh energy and power densities.为了满足新一代电动汽车对高功率输出(>15 kW/kg)的使用需求,将碳基超级电容器的能量密度提高到与电池相当的水平,同时保持高功率密度是发展碳基电容器的核心关键。本文介绍了一种由杨木(PW)衍生的多孔炭,通过KOH活化和还原氧化石墨烯(rGO)掺杂的方法合成(所得样品标记为K-GPWC),用于高比能超级电容器电极。与直接炭化PW制备的样品(PWC,导电率为0.36S/cm)相比,K-GPWC的电导率达到26.3S/cm。作为对称超级电容器的电极,在1.0 mol/L Na_(2)SO_(4)的水性电解质中,基于K-GPWC组装的对称器件,在0.95 kW/kg的功率密度下实现了27.9Wh/kg的高能量密度。在1.0mol/L TEABF4/AN的有机电解质中,基于K-GPWC组装的对称器件实现了电池级储能水平(铅酸电池:30~45Wh/kg,水系锂电池30~55 Wh/kg),在2.0kW/kg的功率密度下最大能量密度为73.9Wh/kg。在40 kW/kg的超高功率密度下,能量密度仍高达67.6 Wh/kg。电池级的能量存储能力主要归结于其优异的电导率和高微孔率(超过80%),这不仅为电子提供了快速的转移通道,还为离子提供了大量的存储表面。本研究工作提供了一种制备炭材料的有效策略,且为具有超高功率和能量密度的超级电容器的实际应用提供了可行性。

关 键 词：Reduced GO modification Loose wood Symmetric supercapacitor Battery-level energy density 

分 类 号：TQ152[化学工程—电化学工业]