posted on 2019-01-29, 00:00authored byHongwei Sheng, Xuetao Zhang, Yonglu Ma, Pengxiang Wang, Jinyuan Zhou, Qing Su, Wei Lan, Erqing Xie, Chuanfang John Zhang
Developing
high-performance, flexible, transparent supercapacitors for wearable
electronics represents an important challenge, as it requires active
materials to be sufficiently transparent without compromising energy
storage. Here, we manipulate the morphology of the active materials
and the junctions on the current collector to achieve optimum electronic/ionic
transport kinetics. Two-dimensional Co(OH)2 nanosheets
with single or two layers were vertically aligned onto a modified
Ag nanowires (AgNWs) network using an electrochemical deposition–UV
irradiation approach. The metallic AgNWs network endows high transparency
while minimizing the contact resistance with the pseudocapacitive
Co(OH)2 nanosheets. The Co(OH)2 nanosheets self-assembled
into a three-dimensional array, which is beneficial for the fast ion
movements. The rational materials design greatly boosts the electrochemical
performance of the hybrid network, including an ultrahigh areal capacitance
up to 3108 μC cm–2 (5180 μF cm–2) coupled with long cycle life (20 000 cycles). As a prototype
device, the symmetric supercapacitor well combines high energy/power
density and excellent mechanical flexibility and long-term performance,
suggesting a promising application for the next-generation wearable
electronics.