Supercapacitor properties of MnO2 nanoflakes on nickel foam-graphene by hydrothermal and chemical wet methods

• Main Authors: Li-Wei Chang, 張立瑋
• Other Authors: 曾文甲
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/85912718335290994415

碩士 === 國立中興大學 === 材料科學與工程學系所 === 103 === MnO2 nanoflakes/graphene were synthesized by hydrothermal and chemical wet methods. At first, graphene was synthesized on the nickel foam by chemical wet method. Then, MnO2 nanoflakes were synthesized on the graphene foam by hydrothermal process for comparison purpose. In comparison, MnO2 nanflakes were synthesis on the nickel foam by hydrothermal process. The samples were denoted as NG, NGM and NM, respectively. We changed the precursor concentration and synthesis time in the hydrothermal process to obtain NM and NGM to achieve the best capacitance performance. The specific capacitance of NM and NGM was to be 334.12 F/g and 726.67 F/g, respectively. The rate capability was 48.51% and 51.58%, respectively. After 1000 cycling tests, the specific capacitance retention was to showed 71.9% and 82.1% for NM and NGM, respectively. The NGM showed high specific capacitance and excellent cycle stability.