摘要
通过两步微波和离子交换的方法得到一种直径约为1.5μm的微球形貌铜离子掺杂钒基配位聚合物(V-Cu-HHTP).聚合物中部分取代的Cu^(2+)提高了配位聚合物的导电性和结构稳定性,并提供V、Cu的协同效应,在用于超级电容器电极材料时表现出良好的电化学性能.在1 A·g^(-1)的电流密度下,V-Cu-HHTP表现出287 F·g^(-1)的比容量,在10 A·g^(-1)的大电流密度下循环3000圈后,V-Cu-HHTP的电容保持率仍有98.6%,比相同测试条件下未掺杂的VHHTP电极表现优异(比容量为227 F·g^(-1),电容保持率为94.2%).选取V-Cu-HHTP作为正极,活性炭(activated carbon,AC)作为负极,组装非对称超级电容器V-Cu-HHTP//AC,电压窗口达到1.6 V.V-Cu-HHTP//AC在功率密度为795.0 W·Kg^(-1)时,最大能量密度为44.1 Wh·Kg^(-1),优于许多钒基超级电容器.优异的电化学性能归因于:双金属配位聚合物的设计为体系提供了优异的协同效应,提高了结构稳定性;Cu离子掺杂提高了导电性;V-Cu-HHTP的多孔特征为体系暴露更多活性位点,提供优异的双电层电容特性.
The microspheres of copper-ion-doped vanadium-based coordination polymers(V-Cu-HHTP)with diameters of approximately 1.5μm are prepared through two steps of microwave treatment.The introduction of Cu^(2+)is achieved by cation exchange and is assumed to improve electronic conductivity and provide the synergic effect derived from the bimetallic feature of the vanadium-based coordination polymers.Results show that the V-Cu-HHTP exhibit good specific capacitance and cycle stability when used as electrode materials in supercapacitors.More specifically,V-Cu-HHTP show a capacitance of287 F·g^(-1)at 1 A·g^(-1)and have a 98.6%capacitance retention of 10 A·g^(-1)after 3000 charging-discharging cycles.In comparison,the V-HHTP electrode shows a lower specific capacitance of 227 F·g^(-1)at 1 A·g^(-1)with a 94.2%capacitance retention of 10 A·g^(-1).An asymmetric supercapacitor is assembled with the V-Cu-HHTP as a cathode and activated carbon(AC)as an anode(denoted as V-Cu-HHTP//AC).The assembled V-CuHHTP//AC device can achieve a potential window of 1.6 V,and the energy density is as high as 44.1 Wh·Kg^(-1)when the power density is 795.0 W·Kg^(-1).We attribute these excellent electrochemical properties to the following.First,the bimetal-based coordination polymer provides an excellent synergistic effect derived from the two metallic elements.Second,Cu doping improves the electronic conductivity and structural stability of the vanadiumbased coordination polymers.The porous characteristics of V-Cu-HHTP provide numerous active sites to the electrode,thus leading to improved energy storage properties.
作者
高云
植传威
刘峂欣
吕丽萍
GAO Yun;ZHI Chuanwei;LIU Tongxin;LÜLiping(School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China)
出处
《上海大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第1期67-79,共13页
Journal of Shanghai University:Natural Science Edition
基金
国家自然科学基金资助项目(51603119)
上海市教委晨光计划资助项目(16CG46)
青年东方学者岗位计划资助项目(QD2016027)
关键词
超级电容器
配位聚合物
钒基电极
铜离子掺杂
协同效应
supercapacitor
coordination polymer
vanadium-based electrode
Cu-doping
synergistic effect
