Liu Mao-Cheng, Xu Yan, Hu Yu-Xia, Yang Qing-Qing, Kong Ling-Bin, Liu Wen-Wu, Niu Wen-Jun, Chueh Yu-Lun
State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals and School of Materials Science and Engineering , Lanzhou University of Technology , Lanzhou 730050 , P. R. China.
Department of Physics , National Sun Yet-Sun University , Kaohsiung 80424 , Taiwan , ROC.
ACS Appl Mater Interfaces. 2018 Oct 17;10(41):35571-35579. doi: 10.1021/acsami.8b09085. Epub 2018 Oct 3.
We demonstrate, for the first time, a new method of fabricating hybrid MoS/poly(ethyleneimine)-modified graphene oxide (PEI-GO) composites assembled through electrostatically charged interaction between the negatively charged MoS nanosheets and positively charged PEI-GO in an aqueous solution. The GO can not only improve the electronic conductivity of the MoS/PEI-GO composites, leading to an excellent charge-transfer network, but also hamper the restacking of MoS nanosheets. The composition ratios between MoS and PEI-GO were also optimized with the highest specific capacitance of 153.9 F g where 96.0% of the initial specific capacitance remains after 6800 cycles. The specific capacitance of only 117.5 F g was observed for the pure MoS nanosheets, and 68.2% of the initial specific capacitance was achieved after 5000 cycles. The excellent electrochemical performance of the hybrid MoS/PEI-GO composites was demonstrated by establishing an asymmetric supercapacitor with a MoS/PEI-GO-based negative electrode and an activated-carbon positive electrode. The asymmetric supercapacitor provided a maximum capacitance of 42.9 F g, and 93.1% of the initial capacitance was maintained after 8000 cycles. Furthermore, a MoS/PEI-GO//activated-carbon asymmetric supercapacitor delivered an energy density of 19.3 W h kg and a power density of 4500 W kg, indicating the potential of the hybrid MoS/PEI-GO composites in electrochemical energy storage applications.
我们首次展示了一种制备杂化MoS/聚（乙烯亚胺）修饰氧化石墨烯（PEI-GO）复合材料的新方法，该复合材料通过带负电荷的MoS纳米片与带正电荷的PEI-GO在水溶液中的静电相互作用组装而成。GO不仅可以提高MoS/PEI-GO复合材料的电子导电性，形成优异的电荷转移网络，还能阻碍MoS纳米片的重新堆叠。MoS与PEI-GO之间的组成比例也进行了优化，其最高比电容为153.9 F/g，在6800次循环后仍保留96.0%的初始比电容。纯MoS纳米片的比电容仅为117.5 F/g，在5000次循环后达到初始比电容的68.2%。通过构建以MoS/PEI-GO为负极、活性炭为正极的不对称超级电容器，证明了杂化MoS/PEI-GO复合材料具有优异的电化学性能。该不对称超级电容器的最大电容为42.9 F/g，在8000次循环后仍保持93.1%的初始电容。此外，MoS/PEI-GO//活性炭不对称超级电容器的能量密度为19.3 W h/kg，功率密度为4500 W/kg，表明杂化MoS/PEI-GO复合材料在电化学储能应用中的潜力。
