High energy density primary cathode with a mixed electron/ion interface.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Developing high-performance cathodes is crucial for advancing lithium primary batteries.
• Fluorinated carbon materials offer potential but face challenges in charge transport and ion diffusion.
• Graphdiyne (GDY) is a novel carbon allotrope with unique electronic and structural properties.

Purpose of the Study:

• To design and synthesize a high-performance fluorinated carbon cathode using a two-dimensional encapsulation strategy.
• To investigate the synergistic effects of a fluorinated carbon/graphdiyne (CF/GDY) heterostructure on electrochemical performance.
• To elucidate the mechanisms behind enhanced charge transport and ion diffusion in the CF/GDY system.

Main Methods:

• Synthesis of a fluorinated carbon/graphdiyne (CF/GDY) heterostructure via a two-dimensional encapsulation method.
• Fabrication of electrodes using the CF/GDY material for lithium primary battery applications.
• Electrochemical characterization, including rate performance testing and energy density measurements.

Main Results:

• The CF/GDY heterostructure demonstrated strengthened three-dimensional contacts, enhancing charge transport kinetics.
• Lithium-ion diffusion dynamics were significantly accelerated within the CF/GDY electrodes.
• The electrodes achieved an enhanced voltage platform of ~2.5 V, excellent rate performance (621.6 mA h g⁻¹ at 5C), and high energy density (2039.3 W h kg⁻¹).

Conclusions:

• Two-dimensional GDY encapsulation is an effective strategy for improving fluorinated carbon cathode performance.
• The hierarchical porosity and electronic structure modulation by GDY contribute to superior storage kinetics and ion transportation.
• This approach shows significant potential for advancing the performance of lithium primary batteries.