Mohamed Aya M, Sayed Doha M, Allam Nageh K
Energy Materials Laboratory (EML), School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt.
Department of Chemistry, Faculty of Science, Cairo University, Cairo 12613, Egypt.
ACS Appl Mater Interfaces. 2023 Apr 5;15(13):16755-16767. doi: 10.1021/acsami.3c00087. Epub 2023 Mar 22.
Rational design and structural regulation of hybrid nanomaterials with superior electrochemical performance are crucial for developing sustainable energy storage platforms. Among these materials, NiCo-layered double hydroxides (NiCo-LDHs) demonstrate an exceptional charge storage capabilities owing to their tunable 2D lamellar structure, large interlayer spacing, and rich redox electrochemically active sites. However, NiCo-LDHs still suffer from sever agglomeration of their particles with limited charge transfer rates, resulting in an inadequate rate capability. In this study, bimetallic ZnCo-metal organic framework (MOF) tripods were grown on the surface of NiCo-LDH nanowires, which significantly reduced the self-agglomeration and stacking of the NiCo-LDH nanowire arrays, offering more accessible active sites for charge transfer and shortening the path for ion diffusion. The fabricated hybrid ZnCo-MOF@NiCo-LDH and its individual counterparts were tested as supercapacitor electrodes. The ZnCo-MOF@NiCo-LDH electrode demonstrated a remarkable specific capacitance of 1611 F g at 2 A g with an enhanced rate capability of 66% from 2 to 20 A g. Moreover, an asymmetric all solid-state supercapacitor device was constructed using ZnCo-MOF@NiCo-LDH and palm tree-derived activated carbon (P-AC) as positive and negative poles, respectively. The constructed device can store a high specific energy of 44.5 Wh Kg and deliver a specific power of 876.7 W Kg with outstanding Columbic efficiency over 10,000 charging/discharging cycles at 15 A g.
设计具有卓越电化学性能的杂化纳米材料并对其结构进行调控,对于开发可持续的储能平台至关重要。在这些材料中,镍钴层状双氢氧化物(NiCo-LDHs)因其可调谐的二维层状结构、较大的层间距以及丰富的氧化还原电化学活性位点而展现出卓越的电荷存储能力。然而,NiCo-LDHs仍存在严重的颗粒团聚问题,电荷转移速率有限,导致倍率性能不足。在本研究中,双金属ZnCo金属有机框架(MOF)三脚架生长在NiCo-LDH纳米线表面,这显著减少了NiCo-LDH纳米线阵列的自团聚和堆叠,为电荷转移提供了更多可及的活性位点,并缩短了离子扩散路径。制备的杂化材料ZnCo-MOF@NiCo-LDH及其单独的对应物被测试用作超级电容器电极。ZnCo-MOF@NiCo-LDH电极在2 A g时表现出1611 F g的显著比电容,在2至20 A g范围内倍率性能提高了66%。此外,使用ZnCo-MOF@NiCo-LDH和棕榈树衍生的活性炭(P-AC)分别作为正极和负极构建了一种非对称全固态超级电容器器件。所构建的器件在15 A g下可存储44.5 Wh Kg的高比能量,输出876.7 W Kg的比功率,在超过10,000次充放电循环中具有出色的库仑效率。