Surface Defect Engineering on Perovskite Oxides as Efficient Bifunctional Electrocatalysts for Water Splitting

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Efficient and cost-effective electrocatalysts are crucial for sustainable hydrogen production through water splitting.
• Perovskite oxides show promise but require optimization for enhanced electrocatalytic activity.

Purpose of the Study:

• To develop a surface defect engineering method for optimizing perovskite oxide electrocatalysts.
• To enhance the performance of perovskite oxide electrocatalysts for water electrolysis.

Main Methods:

• Utilized selective acid etching to engineer surface defects in a ferrite-based perovskite oxide, La$_{0.6}$Sr$_{0.4}$Co$_{0.2}$Fe$_{0.8}$O$_{3-δ}$ (LSCF).
• Identified optimal parameters for surface treatment to create a bifunctional electrocatalyst (LSCF-30).
• Maintained the perovskite bulk crystal lattice integrity during surface modification.

Main Results:

• Selective corrosion of the A-site Sr element in the surface region was achieved.
• Increased exposure and decreased coordination of B-site metals were observed.
• Modulation of the electronic structure of B-site metals and enhanced structural stability were confirmed.

Conclusions:

• Surface defect engineering is an effective strategy for enhancing perovskite oxide electrocatalyst performance.
• The developed method provides a pathway for designing high-performance electrocatalysts for water splitting.
• The study highlights the importance of surface modification while preserving bulk structure for catalyst stability and activity.