Accessing Strain Engineered V-Fe(O)OH from Prussian Blue Analogue Precatalyst for Efficient Anodic Oxidation...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Prussian blue analogues (PBAs) are effective precatalysts for anodic oxidation reactions (AORs).
• Active metal oxyhydroxide [M(O)OH] phases are crucial for AORs.
• Tuning electronic features of PBAs can enhance catalytic activity.

Purpose of the Study:

• To introduce a d-d electron complementation strategy for fine-tuning VOFe-PBA precatalysts.
• To investigate the electronic and structural changes in VOFe-PBA.
• To evaluate the catalytic performance of the derived V-Fe(O)OH active catalyst.

Main Methods:

• Synthesis and characterization of VOFe-PBA precatalyst.
• Spectroscopic studies (e.g., XPS, XAS) to analyze electronic structure.
• Electrochemical activation and performance testing for oxygen evolution reaction (OER) and iodide oxidation reaction (IOR).
• In-situ Raman spectroscopy and mechanistic investigations.

Main Results:

• Spectroscopic studies confirmed altered coordination and electronic features in VOFe-PBA compared to FeFe-PBA.
• Electrochemical activation yielded a strained V-Fe(O)OH active catalyst.
• V-Fe(O)OH exhibited exceptional OER (1.56 V vs RHE) and IOR (1.42 V vs RHE) performance at 100 mA cm⁻².
• V-Fe(O)OH achieved 60% energy efficiency in IOR-assisted water splitting.

Conclusions:

• The d-d electron complementation strategy effectively enhances PBA precatalysts.
• The strained V-Fe(O)OH active catalyst demonstrates superior electrocatalytic activity for AORs.
• The mechanism involves lattice oxygen mechanism (LOM) and proton-decoupled electron transfer (PDET).