三维多级钴酸镍结构的形貌调控及其电化学性能
Morphology control and electrochemical properties of three-dimensional hierarchical NiCo2O4 structure
李群 1张阔 1李艳华 1王书桓 1倪国龙1
作者信息
- 1. 华北理工大学 冶金与能源学院,唐山 063210
- 折叠
摘要
形貌结构的调控对材料的电化学性能具有重要影响.本文采用溶剂热法结合煅烧在不同溶剂比及温度下合成不同形貌结构的钴酸镍,利用XRD及SEM和TEM等对样品的物相组成及形貌结构进行了表征,并对其电化学性能进行了分析.结果表明:当水与乙醇体积比为 1∶1时,样品为中空的海胆状NiCo2O4,随着水比例的增加,形貌逐渐转变为规则的中心放射状的针状形貌,且有第二相物质的存在.在水与乙醇体积比为 1∶1时,随着温度的增加,形貌主要由毛绒球向花状、海胆状、中心放射状的针状过渡,而样品均为纯NiCo2O4.90℃合成的样品具有较好的电化学性能,在 1 A·g-1 电流密度下,比电容高达 1 287.5 F·g-1,当扫速从 20～100 mV·s-1 变化时,电容保持率达到 59.4%,循环 1 500圈,比电容保持率高达 80.1%,此外,在整个电化学反应过程中扩散控制过程起主导作用.
Abstract
The control of the morphology and structure has an important influence on the electrochemical pro-perties of materials.In this work,NiCo2O4 samples with different morphologies and structures were synthesized by solvothermal method combined with calcination at different solvent ratios and temperatures.The phase composi-tion and morphology of the samples were characterized by XRD,SEM and TEM et al,and the electrochemical per-formance was further studied.The results show that the sample is hollow sea urchin-like NiCo2O4,when the volume ratio of water to ethanol is 1∶1.With the increase of the content of water,the morphology gradually changes to regular central radial needle-like morphology,and there is a second phase substance.Under the condition of the volume ratio of water to ethanol is 1∶1,with the increase of temperature,the morphology mainly changes from fluffy ball to a flower-like,sea urchin-like,and center-radiating needle,while the phases of samples are pure NiCo2O4.The sample synthesized at 90℃exhibits better electrochemical performance.The specific capacitance is up to 1 287.5 F·g-1 at a current density of 1 A·g-1.The specific capacitance retention rate reaches 59.4%with the scan rate changes from 20-100 mV·s-1,and the specific capacitance retention rate is up to 80.1%after 1 500 cycles.In addition,the whole electrochemical reaction is dominated by the diffusion-controlled process.
关键词
NiCo2O4/形貌调控/生长机制/电极材料/超级电容器/储能/电化学性能Key words
NiCo2O4/morphology control/growth mechanism/electrode material/supercapacitor/capacitance storage/electrochemical properties引用本文复制引用
基金项目
国家自然科学基金(52104329)
河北省自然科学基金(E2021209141)
河北省高等学校科学技术研究项目(BJK2022003)
出版年
2024
NETL
NSTL
维普
万方数据