采用醇辅助液相沉淀法,将MnO2纳米颗粒沉积在碳纳米管(CNTs)的表面,从而获得MnO2/CNTs复合材料。采用两种配料比将其制备成电极并组装成实验室模拟超级电容器,以循环伏安法、交流阻抗法、恒电流充放电法研究了电极在pH=3的Na2SO4(1mol/L)、中性Na2SO4(1mol/L)、饱和LiNO3这3种不同电解液中超级电容性能。结果表明:乙炔黑作为电子导体比石墨的性能更好,在酸性电解液pH=3的Na2SO4中MnO2/CNTs比电容最高(169F/g),但循环过程中的容量保持能力较差。中性溶液中,电极在饱和LiNO3中表现出更高的比电容和循环能力。
The MnO2 nano particles were deposited on the surface of carbon nanotubes (CNTs) to obtain MnO2/CNTs composite by alcohol assisted liquid phase precipitation method.The two ingredient ratio was used to prepare the electrode and assemble into a supercapacitor.in laboratory.Using cyclic voltammetry,AC impedance method and constant current charge discharge method,the performance of the electrode in Na2SO4(1mol/L,pH=3),neutral Na2SO4(1mol/L) and saturated LiNO3 was studied.The results shown that the acetylene black was better than graphite as electronic conductor,MnO2/CNTs had the highest specific capacity(169F/g) in acidic electrolyte pH=3 of Na2SO4,but the capacity of the cycle was not good.Then in neutral solution,the electrode showed higher specific capacityand cycle ability.in saturated LiNO3.
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