Developing Indium-based Ternary Spinel Selenides for Efficient Solid Flexible Zn-Air Batteries and Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Development of efficient and durable electrocatalysts is crucial for advancing zinc-air batteries and water splitting technologies.
• Existing catalysts often face challenges related to cost, efficiency, and stability, hindering widespread application.
• Ternary spinel nanomaterials offer a promising avenue for designing advanced catalytic materials.

Purpose of the Study:

• To synthesize and characterize a novel ternary spinel cobalt-indium selenide (CoIn2Se4) nanomaterial.
• To evaluate the electrocatalytic activity of CoIn2Se4 for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR).
• To investigate the performance of CoIn2Se4 as an air cathode in solid flexible zinc-air batteries (FZABs) and its application in overall water splitting.

Main Methods:

• Facile and environmentally friendly synthesis of ternary spinel CoIn2Se4 nanomaterial.
• Electrochemical characterization including OER, ORR, hydrogen evolution reaction (HER), and overall water splitting performance evaluation.
• Fabrication and testing of solid flexible zinc-air batteries (FZABs) using CoIn2Se4 as the air cathode.
• Density Functional Theory (DFT) calculations to understand reaction mechanisms and energy barriers.

Main Results:

• CoIn2Se4 nanosheets exhibited superior OER and ORR performance compared to pristine CoSe2 and In2Se3.
• CoIn2Se4 demonstrated excellent catalytic activity, with an OER overpotential of 315 mV at 10 mA cm-2 and an ORR onset overpotential of 0.88 V.
• Solid flexible zinc-air batteries (FZABs) utilizing CoIn2Se4 as the air cathode achieved a high specific capacity (733 mAh gZn-1), energy density (931 Wh kg-1), and over 400 cycles of stability.
• CoIn2Se4-based devices successfully powered LED screens, and the material showed enhanced HER performance and efficient overall water splitting with high stability.

Conclusions:

• The novel ternary spinel CoIn2Se4 nanomaterial is a highly efficient and corrosion-resistant electrocatalyst for both oxygen reactions and hydrogen evolution.
• CoIn2Se4 exhibits significant potential as an air cathode material for high-performance solid flexible zinc-air batteries.
• Indium-based ternary selenides are promising candidates for applications in renewable energy devices and water splitting technologies.