Plasma-Induced Oxygen Defect Engineering in Perovskite Oxide for Boosting Oxygen Evolution Reaction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Perovskite oxides are promising oxygen evolution reaction (OER) catalysts due to cost and tunable electronic properties.
• Understanding catalyst structure-property relationships requires controlled electronic structure modulation without changing nanomorphology.

Purpose of the Study:

• To develop a plasma bombardment strategy for optimizing perovskite oxide catalysts.
• To investigate the effect of plasma treatment on the electronic structure and OER activity of LaCo0.9Fe0.1O3 (LCFO).

Main Methods:

• Plasma bombardment was used to treat LaCo0.9Fe0.1O3 (LCFO).
• Experimental characterization included X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS).
• Oxygen evolution reaction (OER) performance was evaluated by measuring overpotential and current density.

Main Results:

• Plasma treatment of LCFO (P-LCFO) introduced abundant oxygen vacancies, exposing more active sites.
• XPS and XAFS analyses revealed a lower cobalt valence state in P-LCFO, attributed to oxygen vacancies.
• P-LCFO demonstrated enhanced OER activity, achieving a low overpotential of 294 mV at 10 mA cm⁻².

Conclusions:

• Plasma engineering is an effective strategy for tuning the electronic structure of perovskite oxides for catalysis.
• The optimized P-LCFO catalyst exhibits superior OER performance compared to commercial RuO2.
• This approach facilitates the study of structure-property relationships and the development of advanced water-splitting catalysts.