Mahamad Yusoff Nor Fazila, Idris Nurul Hayati, Md Din Muhamad Faiz, Majid Siti Rohana, Harun Noor Aniza, Noerochim Lukman
Energy Storage Research Group, Faculty of Ocean Engineering Technology and Informatics, Universiti Malaysia Terengganu, Kuala Nerus 21300, Terengganu, Malaysia.
Department of Electrical and Electronic Engineering, Faculty of Engineering, National Defence University of Malaysia, Kem Sungai Besi, Kuala Lumpur 57000, Malaysia.
Nanomaterials (Basel). 2023 Feb 15;13(4):732. doi: 10.3390/nano13040732.
Currently, efforts to address the energy needs of large-scale power applications have expedited the development of sodium-ion (Na-ion) batteries. Transition-metal oxides, including MnO, are promising for low-cost, eco-friendly energy storage/conversion. Due to its high theoretical capacity, MnO is worth exploring as an anode material for Na-ion batteries; however, its actual application is constrained by low electrical conductivity and capacity fading. Herein, we attempt to overcome the problems related to MnO with heteroatom-doped reduced graphene oxide (rGO) aerogels synthesised via the hydrothermal method with a subsequent freeze-drying process. The cubic MnO particles with an average size of 0.5-1.5 µm are distributed to both sides of heteroatom-doped rGO aerogels layers. Results indicate that heteroatom-doped rGO aerogels may serve as an efficient ion transport channel for electrolyte ion transport in MnO. After 100 cycles, the electrodes retained their capacities of 242, 325, and 277 mAh g, for MnO/rGO, MnO/nitrogen-rGO, and MnO/nitrogen, sulphur-rGO aerogels, respectively. Doping MnO with heteroatom-doped rGO aerogels increased its electrical conductivity and buffered volume change during charge/discharge, resulting in high capacity and stable cycling performance. The synergistic effects of heteroatom doping and the three-dimensional porous structure network of rGO aerogels are responsible for their excellent electrochemical performances.
目前，为满足大规模电力应用的能源需求所做的努力加速了钠离子（Na-ion）电池的发展。包括MnO在内的过渡金属氧化物有望用于低成本、环保的能量存储/转换。由于其高理论容量，MnO作为钠离子电池的负极材料值得探索；然而，其实际应用受到低电导率和容量衰减的限制。在此，我们试图通过水热法合成并随后进行冷冻干燥工艺制备的杂原子掺杂还原氧化石墨烯（rGO）气凝胶来克服与MnO相关的问题。平均尺寸为0.5 - 1.5 µm的立方MnO颗粒分布在杂原子掺杂rGO气凝胶层的两侧。结果表明，杂原子掺杂rGO气凝胶可作为MnO中电解质离子传输的有效离子传输通道。100次循环后，MnO/rGO、MnO/氮掺杂rGO和MnO/氮、硫掺杂rGO气凝胶电极分别保持了242、325和277 mAh g的容量。用杂原子掺杂rGO气凝胶掺杂MnO提高了其电导率，并缓冲了充放电过程中的体积变化，从而产生了高容量和稳定的循环性能。杂原子掺杂与rGO气凝胶的三维多孔结构网络的协同效应是其优异电化学性能的原因。
