Phosphate Anion-Engineered MXene for Efficient Water Dissociation on Single-Atom Alloy

Area of Science:

• Materials Science
• Catalysis
• Surface Chemistry

Background:

• Catalyst supports are crucial for water dissociation, influencing catalyst activity through electronic modification or direct participation.
• MXene (titanium carbide) shows promise as a support due to its electronic properties, but its direct role in accelerating catalytic dynamics is unknown.

Purpose of the Study:

• To investigate the unexplored potential of MXene supports in directly accelerating catalytic dynamics for water dissociation.
• To engineer MXene with phosphate anions to enhance water dissociation activity on single-atom Ru-Cu alloy catalysts.

Main Methods:

• Synthesis of phosphate anion-engineered MXene.
• Performance testing of the catalyst for water dissociation under light irradiation at room temperature.
• In situ spectroscopic characterizations and density functional theory (DFT) calculations to elucidate the mechanism.

Main Results:

• Phosphate anion-engineered MXene achieved a record-high mass-specific activity of 746 L g_Ru^-1 min^-1 for water dissociation.
• The enhanced activity is attributed to an accelerated hydrogen spillover effect.
• Phosphate anions induced electronic modification of MXene's titanium sites, enhancing catalytic dynamics.

Conclusions:

• MXene-based supports possess a previously unrecognized catalytic role in water dissociation.
• Phosphate anion engineering provides a new strategy for designing advanced catalyst supports.
• Tailored support-catalyst-reactant interactions are key to enhancing water dissociation efficiency.