高性能NiCoP基超级电容器电化学性能

采用水热和低温磷化反应两步法,在无添加沉淀剂条件下成功在泡沫镍上合成纳米花状镍钴磷化物(NiCoP/NF)。研究结果表明,镍/钴元素物质的量之比为1∶1时,在1 A·g~(-1)电流密度下,Ni_(1/2)Co_(1/2)P/NF的比容量高达1 276.36 F·g~(-1),在10 A·g~(-1)电流密度下充放电循环3 000次后,比容量保持率为78.23%。此外,以Ni_(1/2)Co_(1/2)P/NF为正极,活性炭(AC)为负极组装的非对称超级电容器(Ni_(1/2)Co_(1/2)P/NF//AC/NF)在725 W·kg~(-1)的功率密度下,能量密度高达36.25 Wh·kg~(-1)。

Electrochemical Properties of High-Performance NiCoP-Based Supercapacitors

Herein, nanoflower-like nickel-cobalt phosphates coated on nickel foam (NiCoP/NF) were synthesized by two steps of hydrothermal and low temperature phosphating reaction without precipitator. The result showed that when the molar ratio of Ni and Co was 1:1, the Ni_1/2Co_1/2P/NF electrode delivered a high specific capacitance which can reach 1 276.36 F·g^-1 at the current density of 1 A·g^-1. 78.23% of initial specific capacitance was maintained after 3 000 charging and discharging cycles at the current density of 10 A·g^-1. What''s more, an asymmetric supercapacitor (Ni_1/2Co_1/2P/NF//AC/NF) was assembled using Ni_1/2Co_1/2P/NF and activated carbon (AC) as positive and negative electrodes. The device delivered a high energy density of 36.25 Wh·kg^-1 at a power density of 725 W·kg^-1.