Rabani Iqra, Younus Ayesha, Patil Supriya, Seo Young-Soo
Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea.
Department of Physics, University of Agriculture, Faisalabad 38000, Pakistan.
Dalton Trans. 2022 Sep 26;51(37):14190-14200. doi: 10.1039/d2dt01942f.
Manganese dioxide (MnO) is considered a promising aspirant for energy storage materials on account of its higher theoretical capacitance along with low capital cost. However, its performance is generally limited by its poor lifespan and intrinsic conductivity. In this study, MnO-incorporated iron oxide (FeO) nanoflowers were synthesized through a facile hydrothermal route and their electrochemical performance was probed. The surface composition and morphology of the as-synthesized samples were confirmed using X-ray diffraction, X-ray photoemission spectroscopy, and field emission scanning microscopy. The nanoflower-like structure and synergistic effect between the two oxides of the as-prepared MnO@FeO nanocomposite electrode result in desirable surface area and intrinsic conductivity. Owing to its higher surface area and electrical conductivity, the MnO@FeO nanoflower-like nanocomposite exhibits an enhanced specific capacitance () of 1651 F g (1 A g) in a three-electrode test cell, which is two-fold higher than those of pristine FeO and MnO. In addition, an asymmetric supercapacitor (ASC) was readily constructed by sandwiching a cellulose membrane (separator) between MnO@FeO (cathode) and activated carbon (anode). Significantly, the ASC displayed a high of 131 F g (1 A g) along with a pretty high cycling stability of 96% over 5000 cycles at 15 A g and a high energy density of 46.6 Wh kg at 0.8 kW kg. These results demonstrate the significant potential of the MnO@FeO nanoflower ASC device for state-of-the-art futuristic advanced energy storage applications.
二氧化锰（MnO）因其较高的理论电容以及较低的资本成本，被认为是一种很有前景的储能材料。然而，其性能通常受到较差的寿命和固有电导率的限制。在本研究中，通过简便的水热法合成了掺入MnO的氧化铁（FeO）纳米花，并对其电化学性能进行了探究。使用X射线衍射、X射线光电子能谱和场发射扫描显微镜确认了合成样品的表面组成和形态。所制备的MnO@FeO纳米复合电极的纳米花状结构以及两种氧化物之间的协同效应导致了理想的表面积和固有电导率。由于其较高的表面积和电导率，MnO@FeO纳米花状纳米复合材料在三电极测试电池中表现出增强的比电容（），在1 A g时为1651 F g，是原始FeO和MnO的两倍。此外，通过在MnO@FeO（阴极）和活性炭（阳极）之间夹入纤维素膜（隔膜），很容易构建一个不对称超级电容器（ASC）。值得注意的是，该ASC在15 A g下表现出131 F g（1 A g）的高比电容，在5000次循环中具有96%的相当高的循环稳定性，在0.8 kW kg下具有46.6 Wh kg的高能量密度。这些结果证明了MnO@FeO纳米花ASC器件在最先进的未来先进储能应用中的巨大潜力。
