摘要
以Na_2MoO_4·2H_2O、Ni SO_4·6H_2O和MnO_2为原料,采用水热法成功制备了类松果状NiMoO_4/MnO_2复合材料.通过X射线衍射、扫描电子显微镜、恒电流充放电、循环伏安和交流阻抗对材料进行表征.结果表明,MnO_2的最佳质量分数为10%,所得NiMoO_4/MnO_2复合材料具有类松果状形貌,其颗粒直径为200～600 nm,且表面粗糙、多孔;在1 A·g^(-1)的电流密度下,MnO_2质量分数为0、5%、10%、15%、20%时,所得复合材料NM0、NM5、NM10、NM15和NM20的放电比电容分别为260、248、650、420和305 F·g^(-1).在电流密度为10 A·g^(-1)下,最佳样品NM10复合材料的首次放电比容量为102 F·g^(-1),经过100次循环后,其放电比电容稳定在147 F·g^(-1).该性能的提高,主要是由于MnO_2的引入弥补了NiMoO_4单一材料存在的不足,从而达到协同增效的作用.
Supercapacitors,also called electrochemical capacitors or ultracapacitors,have attracted increasing attention owing to their high specific capacitance,high power density,long lifecycle,fast charge-discharge ability,wide working temperature range,and environmental friendliness for mobile electronics,power grids,and hybrid electric vehicles.The electrode is the most important part of supercapacitors;therefore,the electrode material is the chief factor that determines the properties of supercapacitors.To enhance the performance of a supercapacitor,particularly its specific energy while retaining its intrinsic high specific power,several researchers have focused mainly on improving the properties of electrode materials.The major classes of materials applied for supercapacitors include various forms of carbon,transition metal oxides,and conductive polymers.Compared to the carbon materials and conducting polymer materials,transition metal oxides can achieve a much higher specific capacitance because of their high theoretical capacitance,well-defined electrochemical redox activity,low cost,and abundant resources.In particular,binary metal oxides,such as NiMoO4,MnMoO4,and Co MoO4,have been extensively studied as pseudocapacitor electrode materials because of their good electronic conductivity and rich redox reactions.In this study,pinecone-like NiMoO4/MnO2 composite materials were successfully synthesized using a facile hydrothermal method.Na2 MoO4·2 H2O,Ni SO4·6 H2O,and MnO2 were used as raw materials.The as-products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM),galvanostatic charge-discharge,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS).The results show that when the optimal content of MnO2 reaches 10%,the obtained NiMoO4/MnO2 composite materials exhibits a pinecone-like porous morphology,with the particle size ranging from 200 to600 nm.The results show that NiMoO4/MnO2 composite materials have excellent electrochemical properties.The discharge specific
作者
张勇
常翠荣
王诗文
高海丽
闫继
贾晓东
罗河伟
高可政
张爱勤
ZHANG Yong;CHANG Cui-rong;WANG Shi-wen;GAO Hai-li;YAN Ji;JIA Xiao-dong;LUO He-wei;GAO Ke-zheng;ZHANG Ai-qin(Department of Material and Chemical Engineering,Zhengzhou University of Light Industry,Zhengzhou 450002,China;Henan Provincial Key Laboratory of Surfaceand Interface Science and Technolog,Zhengzhou 450002,China)
出处
《工程科学学报》
EI
CSCD
北大核心
2019年第5期646-651,共6页
Chinese Journal of Engineering
基金
国家自然科学基金资助项目(21503193)
河南省高校科技创新团队支持计划资助项目(16IRTSTHN016)
