Electrostatic Self-Assembly to Construct MXene@PS@CF_x Electrode for High Power Density Lithium Primary Cells

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Low power density is a significant barrier to the widespread use of fluorinated carbon (CFx) materials in energy storage.
• Developing advanced electrode materials is crucial for enhancing the performance of primary lithium cells.

Purpose of the Study:

• To propose a novel strategy for fabricating MXene@PS@CFx electrodes.
• To improve the power density and energy density of CFx-based electrodes.
• To understand the electrochemical reaction mechanisms at the cathode interface.

Main Methods:

• Electrostatic self-assembly using polystyrene (PS) microspheres as sacrificial templates.
• Surface modification of CFx with MXene to modulate C-F bonds.
• Atomic force microscopy (AFM) to monitor cathode interface evolution with states of charge (SOC).

Main Results:

• The modified MXene@PS@CFx electrode exhibits modulated C-F bonds and increased sp2 C=C bonds.
• AFM revealed reduced height distribution and moderate roughness, facilitating reaction sites and mitigating volume expansion.
• Achieved a high energy density of 852 Wh kg⁻¹ at a power density of 10692 W kg⁻¹.

Conclusions:

• The MXene@PS@CFx electrode demonstrates superior rate performance and electrochemical properties.
• The surface modification strategy effectively enhances the power density of primary lithium cells.
• This work provides valuable insights for designing high-performance energy storage materials.