Partial nitridation-induced electrochemistry enhancement of ternary oxide nanosheets for fiber energy storage device

• Main Authors: Hao, Pin, Tan, Hua, Liu, Zhihe, Chao, Dongliang, Jia, Dedong, Sang, Yuanhua, Liu, Hong, Fan, Hong Jin
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2019
• Subjects: Fiber-based Power Source; Flexible Energy Storage; DRNTU::Science::Physics
• Online Access: https://hdl.handle.net/10356/82496; http://hdl.handle.net/10220/48894
• Institution: Nanyang Technological University

Fiber‐based power sources are receiving interest in terms of application in wearable electronic devices. Herein, fiber‐shaped all‐solid‐state asymmetric energy storage devices are fabricated based on a partially nitridized NiCo2O4 hybrid nanostructures on graphite fibers (GFs). The surface nitridation leads to a 3D “pearled‐veil” network structure, in which Ni–Co–N nanospheres are mounted on NiCo2O4 nanosheets' electrode. It is demonstrated that the hybrid materials are more potent than the pure NiCo2O4 in energy storage applications due to a cooperative effect between the constituents. The Ni–Co–N segments augment the pristine oxide nanosheets by enhancing both capacity and rate performance (a specific capacity of 384.75 mAh g−1 at 4 A g−1, and a capacity retention of 86.5% as the current is increased to 20 A g−1). The whole material system has a metallic conductivity that renders high‐rate charge and discharge, and an extremely soft feature, so that it can wrap around arbitrary‐shaped holders. All‐solid‐state asymmetric device is fabricated using Ni–Co–N/NiCo2O4/GFs and carbon nanotubes/GFs as the electrodes. The flexible device delivers outstanding performance compared to most oxide‐based full devices. These structured hybrid materials may find applications in miniaturized foldable energy devices.