We demonstrate a simple and highly efficient strategy to synthesize MnO2/nitrogen-doped ultramicroporous carbon nanospheres(MnO2/N-UCNs) for supercapacitor application.MnO2/N-UCNs were fabricated via a template-free...We demonstrate a simple and highly efficient strategy to synthesize MnO2/nitrogen-doped ultramicroporous carbon nanospheres(MnO2/N-UCNs) for supercapacitor application.MnO2/N-UCNs were fabricated via a template-free polymerization of resorcinol/formaldehyde on the surface of phloroglucinol/terephthalaldehyde colloids in the presence of hexamethylenetetramine,followed by carbonization and then a redox reaction between carbons and KMnO4.As-prepared MnO2/N-UCNs exhibits regular ultramicropores,high surface area,nitrogen heteroatom,and high content of MnO2.A typical MnO2/N-UCNs with 57 wt.%MnO2 doping content(denoted as MnO2(57%)/N-UCNs) makes the most use of the synergistic effect between carbons and metal oxides.MnO2(57%)/N-UCNs as a supercapacitor electrode exhibits excellent electrochemical performance such as a high specific capacitance(401 F/g at 1.0 A/g) and excellent charge/discharge stability(86.3%of the initial capacitance after 10,000 cycles at 2.0 A/g) in 1.0 mol/L Na2SO4 electrolyte.The well-designed and high-performance MnO2/N-UCNs highlight the great potential for advanced supercapacitor applications.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.21273162,21473122,21501135)the Science and Technology of Shanghai Municipality,China(No.14DZ2261100)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Large Equipment Test Foundation of Tongji University
文摘We demonstrate a simple and highly efficient strategy to synthesize MnO2/nitrogen-doped ultramicroporous carbon nanospheres(MnO2/N-UCNs) for supercapacitor application.MnO2/N-UCNs were fabricated via a template-free polymerization of resorcinol/formaldehyde on the surface of phloroglucinol/terephthalaldehyde colloids in the presence of hexamethylenetetramine,followed by carbonization and then a redox reaction between carbons and KMnO4.As-prepared MnO2/N-UCNs exhibits regular ultramicropores,high surface area,nitrogen heteroatom,and high content of MnO2.A typical MnO2/N-UCNs with 57 wt.%MnO2 doping content(denoted as MnO2(57%)/N-UCNs) makes the most use of the synergistic effect between carbons and metal oxides.MnO2(57%)/N-UCNs as a supercapacitor electrode exhibits excellent electrochemical performance such as a high specific capacitance(401 F/g at 1.0 A/g) and excellent charge/discharge stability(86.3%of the initial capacitance after 10,000 cycles at 2.0 A/g) in 1.0 mol/L Na2SO4 electrolyte.The well-designed and high-performance MnO2/N-UCNs highlight the great potential for advanced supercapacitor applications.