Kim Myeongjin, Kim Jooheon
School of Chemical Engineering & Materials Science, Chung-Ang University , Seoul 156-756, Korea.
ACS Appl Mater Interfaces. 2014 Jun 25;6(12):9036-45. doi: 10.1021/am406032y. Epub 2014 Jun 11.
Silicon carbide microsphere/birnessite-type MnOx (SiC/B-MnOx) composites were prepared by removal of a SiO2 layer with redox deposition of birnessite-type MnOx for supercapacitor electrode materials. The characterization studies showed that the birnessite-type MnOx in the composite was homogeneously deposited on the SiC surface. The capacitive properties of the as-prepared SiC/B-MnOx electrodes were measured in a three-electrode system using 1 M Na2SO4(aq) as the electrolyte. The SiC/B-MnOx(6) electrode, fabricated using a MnOx/SiC feeding ratio of 6:1, displayed a specific capacitance of 251.3 F g(-1) at 10 mV s(-1). Such excellent electrochemical performance is attributed to an increase in the electrical conductivity in the presence of silicon carbide, an increase in the effective interfacial area between MnOx and the electrolyte, and the contact area between MnOx and silicon carbide. The deposition of birnessite-type MnOx on a SiC surface may be a prospective fabrication technique for electrode materials for supercapacitors.
通过用氧化还原沉积水钠锰矿型MnOₓ去除SiO₂层制备了用于超级电容器电极材料的碳化硅微球/水钠锰矿型MnOₓ（SiC/B-MnOₓ）复合材料。表征研究表明，复合材料中的水钠锰矿型MnOₓ均匀沉积在SiC表面。以1 M Na₂SO₄（水溶液）为电解质，在三电极体系中测量了所制备的SiC/B-MnOₓ电极的电容性能。使用MnOₓ/SiC进料比为6:1制备的SiC/B-MnOₓ(6)电极在10 mV s⁻¹时显示出251.3 F g⁻¹的比电容。这种优异的电化学性能归因于碳化硅存在下电导率的增加、MnOₓ与电解质之间有效界面面积的增加以及MnOₓ与碳化硅之间的接触面积。水钠锰矿型MnOₓ在SiC表面的沉积可能是一种用于超级电容器电极材料的有前景的制备技术。
