Graphite-Phosphate Composites: Structure and Voltammetric Investigations.

Area of Science:

• Materials Science
• Electrochemistry
• Recycling and Circular Economy

Background:

• Increasing global use of lithium-ion batteries (LIBs) necessitates efficient recycling technologies.
• Waste graphite from retired LIB electrodes presents an opportunity for resource recovery and pollution prevention.
• Developing methods to convert waste graphite into valuable materials aligns with circular economy principles.

Purpose of the Study:

• To prepare novel electrode materials from waste anode graphite sourced from spent mobile phone batteries.
• To investigate the structural and electronic properties of these recycled graphite composites.
• To evaluate the electrochemical performance of the prepared materials as electrodes in LIBs and fuel cells.

Main Methods:

• Waste anode graphite from spent mobile phone batteries was used to synthesize composite materials via the melt quenching method.
• The composition of the synthesized materials followed the formula xBT·0.1C₁₂H₂₂O₁₁·(0.9-x)(NH₄)₂HPO₄, with BT ranging from 0-50 weight%.
• X-ray diffractometry was employed for structural analysis, and electrochemical performance was assessed in LIB and fuel cell setups.

Main Results:

• All prepared samples exhibited a hexagonal crystalline graphite phase.
• Increasing BT content led to a decrease in particle size and a lower average band gap (1.32 eV ±0.3 eV), attributed to higher network disorder.
• Composites demonstrated excellent electrochemical performance, with 50% BT doping showing optimal suitability for electrode applications.

Conclusions:

• Waste graphite from spent LIBs can be effectively repurposed into advanced electrode materials.
• The melt quenching method is viable for creating these graphite-based composites with tunable properties.
• The developed materials show significant promise for enhancing energy storage and conversion devices within a sustainable framework.