High-performance light-driven heterogeneous CO₂ catalysis with near-unity selectivity on metal phosphides

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Achieving precise control over reaction sites in heterogeneous catalysis is crucial for optimizing activity, selectivity, and stability, mirroring advancements in homogeneous catalysis.
• Solar-driven CO₂ hydrogenation offers a sustainable pathway for chemical production, but requires efficient catalytic materials.

Purpose of the Study:

• To introduce metal phosphides as a class of materials for precise control in heterogeneous catalysis.
• To explore the potential of metal phosphides in solar-driven CO₂ hydrogenation.
• To investigate the catalytic performance of Ni₁₂P₅ for the reverse water gas shift reaction.

Main Methods:

• Synthesis and characterization of Ni₁₂P₅ material.
• Photocatalytic testing of Ni₁₂P₅ for CO₂ hydrogenation under solar irradiation.
• Analysis of reaction products to determine CO production rate and selectivity.
• Investigation of catalytic stability over extended periods.
• Exploration of Co₂P analogs to demonstrate material class potential.

Main Results:

• Ni₁₂P₅ exhibits intense light harvesting across the solar spectrum due to its structure of dispersed nickel nanoclusters in a phosphorus lattice.
• Ni₁₂P₅ functions as an effective photothermal catalyst for the reverse water gas shift reaction.
• Achieved a high CO production rate of 960 ± 12 mmol g_cat^-1 h^-1 with near 100% selectivity.
• Demonstrated long-term stability of the Ni₁₂P₅ catalyst.
• Co₂P analogs showed similar promising catalytic behavior, indicating a broader applicability of metal phosphides.

Conclusions:

• Metal phosphides, exemplified by Ni₁₂P₅, enable precise control over catalytic processes in solar-driven CO₂ hydrogenation.
• The unique structure and panchromatic absorption of Ni₁₂P₅ facilitate efficient photothermal catalysis.
• Metal phosphides represent a versatile platform for developing high-rate and highly selective catalysts for CO₂ conversion.