三维氮掺杂分级多孔碳纳米片的制备及储锌性能  

Preparation and Zinc Storage Properties of Three-dimensional Nitrogen-doped Hierarchical Porous Carbon Nanosheets

作　　者：何军 朱傲阳 魏雨晨 朱怡全 蒋莉[2] 何孝军[1] HE Jun;ZHU Aoyang;WEI Yuchen;ZHU Yiquan;JIANG Li;HE Xiaojun(School of Chemistry and Chemical Engineering,Anhui Key Laboratory of Coal Clean Conversion and High Valued Utilization,Anhui University of Technology,Maanshan 243002,China;College of Continuing Education,Anhui University of Technology,Maanshan 243002,China)

机构地区：[1]安徽工业大学化学与化工学院,煤清洁转化与高值化利用安徽省重点实验室,马鞍山243002 [2]安徽工业大学继续教育学院,马鞍山243002

出　　处：《高等学校化学学报》2024年第7期133-144,共12页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:52372037,52072002);安徽省高等学校优秀科研创新团队项目(批准号:2023AH010015)资助.

摘　　要：以MgO@ZIF-8为双模板和辅助碳源,KHCO_(3)为活化剂,煤沥青(CTP)为碳源,制备了三维氮掺杂分级多孔碳纳米片(N-CNs),探究了KHCO_(3)与CTP的质量比对N-CNs的结构、化学组成和锌离子储存性能的影响.结果表明,当KHCO_(3)与CTP的质量比为3∶1时,制备的样品(N-CN_(3))具有三维互连的碳纳米片结构、高比表面积(2360m^(2)/g)和吡咯氮含量.将N-CN_(3)作为锌离子混合电容器(ZHCs)正极时,其在2mol/LZnSO_(4)电解液中展现了出色的比容量(当电流密度为0.2A/g时,比容量为157.6mA·h/g)、高的能量密度(在176.1W/kg功率密度下能量密度为126.5 W·h/kg)和优异的循环稳定性(当电流密度为5 A/g时,经过20000次循环后容量仅衰减6.4%,库仑效率为99.6%).密度泛函理论计算结果证实,吡咯氮掺杂增加了电极材料对锌离子的吸附能,提高了N-CNs对锌离子的吸附容量.In this work,three-dimensional nitrogen-doped hierarchical porous carbon nanosheets(N-CNs)were synthesized from coal tar pitch(CTP)by using MgO@ZIF-8 as double template and auxiliary carbon source coupled with KHCO_(3) in situ activation.The effects of the mass ratio of KHCO_(3) to CTP on the structure,chemical composition and zinc ion storage properties of N-CNs were investigated.The as-prepared N-CN_(3) at a mass ratio of 3∶1 of KHCO_(3) to CTP features a three-dimensional interconnected carbon nanosheet structure,high specific surface area(2360 m^(2)/g)and pyrrole nitrogen content.Benefiting from the above characteristics,the N-CN_(3) cathode of zinc-ion hybrid capacitor(ZHCs)in 2 mol/L ZnSO_(4) exhibits excellent specific capacity(157.6 mA·h/g at 0.2 A/g),high energy density(126.5 W·h/kg at 176.1 W/kg)and exceptional cycle stability(only 6.4%capacity decay after 20000 cycles at 5 A/g and 100%Coulomb efficiency).The density functional theory(DFT)calculation results verified the enhance-ment of the adsorption energy to Zn^(2+) due to the presence of pyrrole nitrogen in N-CNs,thus leading to enhanced adsorption capacity of N-CNs to zinc ions.This work prides an efficient method for the high-added value utilization of coal chemical by-products.

关 键 词：锌离子混合电容器 煤沥青 多孔碳 MgO@ZIF-8 密度泛函理论计算 

分 类 号：O646[理学—物理化学]