Vertically Oriented and Interpenetrating CuSe Nanosheet Films with Open Channels for Flexible All-Solid-State...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Copper selenide (CuSe) nanostructures are promising p-type semiconductors for optoelectronics, sensing, and photocatalysis.
• Controllable synthesis of CuSe nanosheets with specific orientations and open frameworks is challenging.
• The application of CuSe nanostructures in supercapacitors (SCs) has not been previously explored.

Purpose of the Study:

• To develop a method for synthesizing highly vertically oriented and interpenetrating CuSe nanosheet (NS) films.
• To investigate the performance of these CuSe NS films as binder- and carbon black-free electrodes for flexible, all-solid-state supercapacitors.
• To evaluate the electrochemical properties, flexibility, and stability of the fabricated supercapacitors.

Main Methods:

• Deposition of highly vertically oriented and interpenetrating CuSe NS films on an Au-coated polyethylene terephthalate substrate.
• Fabrication of flexible, symmetric all-solid-state supercapacitors using CuSe NS films and a polyvinyl alcohol-LiCl gel electrolyte.
• Characterization of the electrochemical performance, including specific capacitance, cycling stability, flexibility, and mechanical stability.

Main Results:

• The CuSe NS films exhibited a high specific capacitance of 209 F g^-1.
• The fabricated all-solid-state SCs demonstrated high volumetric specific capacitance (30.17 mF cm^-3), good cycling stability, and excellent flexibility.
• A series of three devices successfully powered a red light-emitting diode, showcasing practical application potential.

Conclusions:

• The vertically oriented and interpenetrating CuSe NS configuration enhances surface area and ion diffusion, leading to superior supercapacitor performance.
• The developed CuSe NS films are suitable for fabricating high-performance, flexible, and stable binder- and carbon black-free electrodes for energy storage.
• This work opens new avenues for utilizing CuSe nanostructures in flexible electronics and energy storage applications.