Metal Doping Regulates Electrocatalysts Restructuring During Oxygen Evolution Reaction.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• High-efficiency and low-cost catalysts are crucial for electrochemical water splitting and hydrogen production.
• Transition metal dichalcogenides show promise but suffer from poor stability during the oxygen evolution reaction (OER).

Purpose of the Study:

• To investigate catalyst restructuring during OER.
• To develop stable and efficient bimetallic sulfide electrocatalysts (Co_xNi_1-xS_y) for the oxygen evolution reaction (OER).

Main Methods:

• Synthesized bimetallic Co_xNi_1-xS_y catalysts with varying Ni:Co ratios.
• Employed surface-sensitive X-ray photoelectron spectroscopy (XPS) and bulk-sensitive X-ray absorption spectroscopy (XAS) to analyze catalyst structure and electronic properties before and after OER.

Main Results:

• Confirmed favorable restructuring of transition metal sulfides after OER.
• Demonstrated that incorporating small amounts of nickel (Ni) into cobalt (Co) sulfides optimizes the local electronic structure.
• Showed that Ni doping regulates restructuring, improving the balance between OER activity and catalyst stability.

Conclusions:

• Nickel doping in cobalt sulfides effectively controls restructuring for enhanced OER performance.
• Developed a doping-regulated restructuring strategy for efficient, noble metal-free OER electrocatalysts.