磷酸根掺杂MnFe2O4及其赝电容特性

Preparation and Pseudocapacitive Properties of Phosphate Ion-doped MnFe2O4

采用水热法先合成MnFe2O4(MFO),然后通过与PH3反应制备了磷酸根离子掺杂的MnFe2O4(PMFO),以提高它的电化学性能。研究结果表明,磷酸根掺杂不仅增大了MnFe2O4的比表面积,也增加了材料的电导性。在1 A/g电流密度下,PMFO比容量为750 F/g,与MFO相比,比电容提高了近70%,同时循环稳定性也得到了极大改善。以PMFO为正极、活性碳为负极的非对称超级电容器(ASCs),在功率密度为2.7 kW/kg时,能量密度达到168.8 Wh/kg。因此,PMFO是有极大应用前景的超级电容器电极材料。

In order to improve the electrochemical performance,the phosphate ion doped MnFe2O4(PMFO)was synthesized by a hydrothermal method combined with a subsequent phosphatization treatment.Both the specific surface area and electrical conductivity of electrode material are improved by the phosphate ion functionalization.Furthermore,the specific capacitance is 750 F/g at 1 A/g for PMFO,which is almost 1.7%higher than that of MFO.Besides,the cyclic stability of PMFO electrode is also improved.The asymmetric supercapacitors(ASCs)assembled by positive electrode PMFO and actived negative electrode carbon(AC)display an ultrahigh energy density of 168.8 Wh/kg at a power density of 2.7 kW/kg.The PMFO is demonstrated as a promising electrode material for supercapacitor applications.