碳纳米管穿插ZIF-67衍生的镍钴锰硒化物及其电化学性能

Carbon Nanotubes Interspersed with ZIF-67-Derived Nickel-Cobalt-Manganese-Selenides and Their Electrochemical Properties

超级电容器具有容量大、功率密度高、循环寿命长的优点,在新能源存储和电动汽车等领域具有广泛的应用前景,而电极材料是提高超级电容器性能的关键。以ZIF-67为模板,通过简便的低温水热反应法以及热处理硒化法,制备了Ni Co Mn Se电极材料,并通过往ZIF-67模板中添加碳纳米管(CNT)或者氧化石墨烯(GO)来达到最佳的电化学性能。结果表明:最佳的NiCoMnSe/CNT电极在1 A/g下的比电容为624.0 F/g,在10 A/g时的倍率性能为90.1%。15 A/g下循环1000次的容量保持率为88%。这种优异的电容性能归功于CNT的存在在NiCoMnSe周围引入了额外的介孔,加强了电解质与活性材料之间的接触。由于超级电容器的非对称性,NiCoMnSe/CNT//活性炭器件在800 W/kg的功率密度下表现出较高的能量密度(43.3 W·h/kg),并具有良好的容量保持率(1000次循环后保持91.4%)。

Supercapacitors have a wide range of potential applications in new energy storage and electric cars due to their high capacity,high power density,and extended cycle life,and the electrode materials are a key to enhancing the supercapacitor performance.NiCoMnSe electrode materials were prepared by a simple low-temperature hydrothermal reaction method and a heat-treatment selenization method using ZIF-67 as a template.The optimum electrochemical performance was obtained via adding carbon nanotube(CNT)or graphene oxide(GO)to the ZIF-67 template.The results show that the optimum NiCoMnSe/CNT electrode has a specific capacitance of 624.0 F/g at 1 A/g and a multiplicative performance of 90.1%at 10 A/g.The capacity retention rate is 88%at 15 A/g for 1000 cycles.This superior capacitive performance is attributed to the presence of CNT introducing additional mesopores around NiCoMnSe,thus enhancing the contact between the electrolyte and the active material.The NiCoMnSe/CNT/activated carbon device exhibits a high energy density(43.3 W·h/kg)at a power density of 800 W/kg and a good capacity retention(i.e.,91.4%after 1000 cycles)due to the asymmetric nature of the supercapacitor.