Switching on electrocatalytic activity in solid oxide cells.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Conversion

Background:

• Solid oxide cells (SOCs) are efficient energy conversion devices operating as fuel cells or electrolysis cells.
• Achieving high performance, durability, and cost-effective manufacturing of SOC electrodes presents significant challenges.
• Current methods for electrode fabrication are often lengthy, intricate, and ex situ, leading to degradation issues.

Purpose of the Study:

• To develop a novel, rapid method for fabricating high-performance SOC electrodes.
• To demonstrate the feasibility of creating unified fuel cell and electrolysis devices.
• To investigate the in operando synthesis of electrode nanostructures for enhanced SOC performance and longevity.

Main Methods:

• Electrochemical poling of a SOC at 2 volts for a few seconds to induce redox exsolution.
• In operando growth of anchored metal nanoparticles on oxide electrodes.
• Performance testing of the fabricated electrodes in both fuel cell and electrolysis modes at 900°C.

Main Results:

• Successfully grew finely dispersed, anchored metal nanoparticles on electrode surfaces.
• Achieved high power density (2 W/cm²) in fuel cell mode and high current density (2.75 A/cm² at 1.3 V) in electrolysis mode.
• Demonstrated stable performance without degradation over 150 hours of testing.

Conclusions:

• In operando nanomaterial synthesis via electrochemical poling offers a rapid and effective route to high-performance SOC electrodes.
• This method enables the unification of fuel cell and electrolysis functionalities in a single, versatile device.
• The approach facilitates simple, cost-effective manufacturing and potential in-situ rejuvenation of SOCs.