Structurally engineered Co-CeO₂ dispersed on N-lemon biochar for efficient energy storage and water splitting

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing efficient electrocatalysts and energy storage materials is crucial for renewable energy technologies.
• Biochar-derived materials offer a sustainable and cost-effective platform for catalyst support.
• Simultaneous energy conversion and storage in a single material is highly desirable.

Purpose of the Study:

• To synthesize and characterize cobalt-doped cerium oxide anchored on nitrogen-doped lemon-peel biochar (Co-CeO2/N-LB).
• To evaluate the material's performance as a multifunctional platform for simultaneous electrocatalysis and energy storage.
• To elucidate the synergistic mechanisms enhancing catalytic activity and charge storage.

Main Methods:

• Synthesis of Co-CeO2/N-LB composite material.
• Electrocatalytic testing for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).
• Electrochemical energy storage measurements, including specific capacitance and cycling stability.
• Post-stability analysis to confirm material integrity.

Main Results:

• Co-CeO2/N-LB exhibited lower overpotentials (289 mV for OER, 64.51 mV for HER) and high TOF.
• The material achieved a high specific capacitance of 1664.16 F g-1 with excellent energy and power density.
• Demonstrated remarkable cycling stability over 9500 cycles with near-equal diffusive and capacitive contributions to charge storage.
• Co-CeO2/N-LB on carbon paper showed sustained performance over 10,000 cycles.

Conclusions:

• The synergistic effects in Co-CeO2/N-LB enhance charge transfer and stability for efficient electrocatalysis.
• The material serves as a promising dual-functional electrode for integrated electrocatalysis and rapid energy storage.
• The N-doped biochar support contributes to the material's overall performance and stability.