Wang Shuonan, Hai Yun, Zhou Bin, Liu Hao, Liao Libing
Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences Beijing 100083 PR China
School of Science, China University of Geosciences Beijing 100083 PR China
RSC Adv. 2020 Nov 26;10(70):43012-43020. doi: 10.1039/d0ra07758e. eCollection 2020 Nov 23.
In the present work, low-cost natural molybdenite was used to make a MoS/N-doped graphene composite through coulombic attraction with the aid of (3-aminopropyl)-triethoxysilane and the electrochemical performance was greatly improved by solvent-free microwave irradiation for tens of seconds. The characterization results indicated that most (3-aminopropyl)-triethoxysilane can decompose and release N atoms to further improve the N-doping degree in NG during the microwave irradiation. In addition, the surface groups of N-doped graphene were removed and the particle size of MoS was greatly decreased after the microwave irradiation. As a result, the composite electrode prepared with microwave irradiation exhibited a better rate performance (1077.3 mA h g at 0.1C and 638 mA h g at 2C) than the sample prepared without microwave irradiation (1013.6 mA h g at 0.1C and 459.1 mA h g at 2C). Therefore, the present results suggest that solvent-free microwave irradiation is an effective way to improve the electrochemical properties of MoS/N-doped graphene composite electrodes. This work also demonstrates that natural molybdenite is a promising low-cost anode material for lithium-ion batteries.
在本工作中,低成本的天然辉钼矿通过(3-氨丙基)-三乙氧基硅烷的库仑引力用于制备MoS₂/N掺杂石墨烯复合材料,并且通过无溶剂微波辐射数十秒,电化学性能得到了极大改善。表征结果表明,在微波辐射过程中,大多数(3-氨丙基)-三乙氧基硅烷会分解并释放N原子,从而进一步提高NG中的N掺杂程度。此外,微波辐射后,N掺杂石墨烯的表面基团被去除,MoS₂的粒径大幅减小。结果,用微波辐射制备的复合电极表现出比未用微波辐射制备的样品更好的倍率性能(0.1C时为1077.3 mA h g,2C时为638 mA h g)(0.1C时为1013.6 mA h g,2C时为459.1 mA h g)。因此,目前的结果表明,无溶剂微波辐射是改善MoS₂/N掺杂石墨烯复合电极电化学性能的有效方法。这项工作还表明,天然辉钼矿是一种有前景的低成本锂离子电池负极材料。