Vacancy engineering in Co-doped CuS_1-x with fast Electronic/Ionic migration kinetics for efficient Lithium-Ion...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Slow lithium-ion diffusion and disordered electron migration hinder Li-ion battery rate capability.
• Developing advanced electrode materials is crucial for higher energy conversion and storage efficiency.

Purpose of the Study:

• To design a novel electrode material, Co-doped CuS_1-x, to overcome diffusion limitations in Li-ion batteries.
• To enhance electronic and ionic conductivity for improved rate capability and cycling stability.

Main Methods:

• Synthesis of Co-doped CuS_1-x with controlled sulfur vacancies.
• Electrocatalytic studies and plane charge density difference simulations to analyze electron transfer.
• Electrochemical performance testing as an anode material in Li-ion batteries.

Main Results:

• Co-doping induced S vacancies, expanding atomic layer spacing and promoting Li-ion diffusion and electron migration.
• Enhanced Li⁺ adsorption energy (2.21 eV) and frequent electron transfer near Co sites were observed.
• Co-doped CuS_1-x anode achieved a capacity of 1309 mAh·g^-1 at 1A g^-1 and retained 1064 mAh·g^-1 after 500 cycles.

Conclusions:

• Co-doped CuS_1-x with S vacancies is a promising electrode material for high-performance Li-ion batteries.
• The material design strategy effectively accelerates ion and electron transport, enhancing electrochemical performance.
• This work offers new avenues for developing advanced electrode materials for rechargeable metal-ion batteries.