Abstract:K+ intercalated-MnO2 nanomaterials were synthesized by using KMnO4 and MnCl2 as redox in KOH solution, placed at 200 ℃ for 48h, then protonated with ammonium persulfate. In addition, layered MnO2/graphene oxide (GO) composites were prepared by using graphene oxide aqueous solution as solvent. The phase and morphology of the prepared materials were characterized by XRD, SEM, etc. The electrochemical performance of the supercapacitor was tested by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) in 1 M KOH solution. The results show that the K+ intercalated MnO2 has the morphology of nanobelts, its length can reach 5-12 μm, and its width is about 500 nm. After protonation, high crystallinity and nanobelt morphology can be maintained. In addition, the electrochemical properties of MnO2 can be significantly improved by the addition of GO. The specific capacitance of layered MnO2 nanobelts/GO composites is as high as 750 F/g at current density of 0.5 A/g.
贾璐璐, 杨宝鹏. 层状MnO2纳米带的插层质子化及其与氧化石墨烯复合材料的电化学性能[J]. 粉末冶金材料科学与工程, 2019, 24(6): 491-497.
JIA Lulu, YANG Baopeng. Protonation of layered MnO2 nanobelts and GO/MnO2 composites and their electrochemical properties. Materials Science and Engineering of Powder Metallurgy, 2019, 24(6): 491-497.
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