TEA Guiding Bimetallic MOF with Oriented Nanosheet Arrays for High-Performance Asymmetric Supercapacitors
Xiling Mao, Hao Liu, Tingting Niu, Xinyu Yan, Mengwei Li
Abstract
The development of supercapacitors with ultrahigh power density, high energy density, and compatible integration for wearable microelectronic devices is significant but challenging. Herein, a bimetallic metal–organic framework (Ni/Co-MOF) with oriented nanosheets was obtained via triethylamine (TEA) guiding using a hydrothermal treatment, in which the TEA guides the vertically oriented array structures of the Ni/Co-MOF and ensures a fast ion/electron transmission path. Subsequently, an asymmetric supercapacitor was rationally designed by applying the bimetallic MOF cathode and an activated carbon (AC) anode. The obtained Ni/Co-MOF sample offers a high storage capacity of 2034 F g−1 at 0.5 A g−1 by harnessing the optimized Ni/Co-MOF with uniformly oriented nanosheet arrays. The constructed asymmetric supercapacitors exhibited a large voltage window of 1.4 V in 3.0 M KOH and an outstanding energy density of 29.5 Wh kg−1 at a power density of 199.1 W kg−1 was obtained, with a remarkable capacitance retention of 89% after 2000 cycles.