还原氧化石墨烯／Mn3O4纳米复合材料的合成及其在超级电容器中的应用

Synthesis of reduced graphene oxide/Mn_3O_4 nanocomposites for supercapacitors

以改进的Hummers法所制氧化石墨烯/硫酸锰(GO/MnSO4)悬浊液为原料,原位合成GO/MnO2复合物,再经低温热处理制备还原氧化石墨烯/Mn3O4(rGO/Mn3O4)纳米复合材料。通过改变GO/MnSO4悬浊液中MnSO4的质量含量实现rGO/Mn3O4复合物中Mn3O4质量分数的可控调变。该法充分利用氧化石墨烯原液中的锰离子,可节省原料,同时可避免氧化石墨烯繁琐的分离过程并简化实验步骤。所得复合材料作为超级电容器电极材料展现良好的电化学电容性能,在饱和K2SO4电解质溶液和50 mA·g-1的电流密度下,Mn3O4质量含量为88%时其比电容达284 F·g-1。

Reduced graphene oxide/Mn3 O4 （ rGO/Mn3 O4 ） nanocomposites were prepared from MnSO4 and GO produced by a modified Hummers method. The GO was deoxygenated by heat treatment, and MnO2 generated by hydrolysis of MnSO4 was simul-taneously reduced to Mn3 O4 . The Mn3 O4 content in the composites could be tailored by the volume of supernatant in the pristine GO/MnSO4 suspension. The maximum specific capacitance of the rGO/Mn3 O4 composite is 284 F·g^-1 at 50 mA·g^-1 as an anode material in a saturated K2 SO4 solution. This approach separates GO from the suspension without complicated procedures, and cheap MnSO4 is used as a Mn3 O4 source.