A precisely Assembled Wall-Like Architecture for High Lithium/Sodium Storage.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• MXene nanosheets and ordered porous carbons offer complementary properties for energy storage applications.
• Combining these materials can overcome individual limitations and enhance electrode performance.

Purpose of the Study:

• To develop a novel composite material by assembling MXene nanosheets and ordered porous carbon.
• To investigate the self-assembly strategy for creating unique wall-like porous structures.
• To evaluate the performance of the composite as an anode material in lithium-ion and sodium-ion batteries.

Main Methods:

• An electrostatic separation-adsorption strategy was employed for ordered alternating self-assembly.
• The resulting MXene-porous carbon composite (MPOC) was characterized for its nanostructure and conductivity.
• Red phosphorus (RP) was used as the active material, and the MPOC@RP anode was tested in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs).

Main Results:

• A unique wall-like porous material (MPOC) with high conductivity and interconnected nanostructure was successfully synthesized.
• The N-doping from porous carbon enhanced the cycle life of the composite.
• The MPOC@RP anode demonstrated high capacity (2454.3 mAh g⁻¹ in LIBs, 2408.1 mAh g⁻¹ in SIBs at 0.1 C) and long cycle stability (low decay rates at 2 C).

Conclusions:

• The developed MPOC material significantly enhances electron and ion transfer rates for superior battery performance.
• This strategy shows great potential for application with other active materials like silicon, sulfur, and selenium.
• The electrostatic separation-adsorption method is effective for designing various MXene-based composite materials.