Urea-assisted hydrothermal synthesis of MnMoO4/MnCO3 hybrid electrochemical electrode and fabrication of high-performance asymmetric supercapacitor

• 作者: Mohan Reddy Pallavolu Arghya Narayan Banerjee Ramesh Reddy Nallapureddy Sang W.Joo
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2022,（1）
• 页码范围: 332-344
• 页数: 13页
• 语种: 英文

摘要

Transition metal molybdates/carbonates and hybrid nanomaterials have attracted great attention in en-ergy storage applications because of their enriched redox activity,good electronic conductivity,and sta-ble crystallinity.We synthesize a multicomponent MnMoO4/MnCO3 hybrid by a one-step hydrothermal method with urea as the reaction fuel.By controlling only the urea concentration in the initial pre-cursor solution,the MnMoO4/MnCO3 molecular ratio is controlled effectively,which is found to have a profound effect on the electrochemical properties of the hybrid electrodes.The electrochemical mea-surements show that the specific capacitance of MnMoO4/MnCO3 hybrid is 1311 F/g,the energy density of 116.8 Wh/kg,and power density of 383 W/kg at a current density of 1 A/g with 79％ capacitance re-tention over 5000 cycles.The fabricated asymmetric supercapacitor device exhibits good energy storage performance,including the specific capacitance of 97 F/g along with the energy density of 26.5 Wh/kg and the power density of 657 W/kg at a current density of 1 A/g and good reversibility with capaci-tance retention of 85％ after 2000 cycles and 70％ over 5000 cycles.The increase in the energy density of 900％ with a mere 60％ decrement in the energy density indicates its potential superior applications in high-power devices.