One-Step Strategy to Maximize Single-Atom Catalyst Utilization in Nitrate Reduction via Bidirectional Optimization of...

Area of Science:

• Materials Science
• Catalysis
• Electrochemistry

Background:

• Single-atom catalysts (SACs) show high performance but suffer from synthesis complexity and mass transfer limitations.
• Efficient utilization of active sites is crucial for SACs in applications like electrocatalytic nitrate reduction (NO3RR).

Purpose of the Study:

• To design a highly efficient copper single-atom catalyst (HE Cu1-N4) for electrocatalytic nitrate reduction.
• To enhance active site exposure and optimize the electronic properties of the catalyst for improved nitrate conversion.

Main Methods:

• A simple one-step pyrolysis method was employed for catalyst synthesis.
• Advanced characterization techniques, synchrotron radiation, and DFT calculations were used for analysis.
• Electrocatalytic performance was evaluated for nitrate reduction.

Main Results:

• The HE Cu1-N4 catalyst exhibited enhanced Cu atom exposure and reduced mass transfer resistance due to its 3D structure.
• A locally electron-deficient environment in Cu atoms increased electrostatic attraction to nitrate ions.
• Achieved 100% NH3 selectivity and a 7-fold higher NH3 yield compared to conventional SACs.
• Demonstrated excellent stability and interference resistance in complex water systems under pilot-scale conditions.

Conclusions:

• A straightforward synthesis strategy significantly improved the utilization efficiency of single atoms in SACs.
• The HE Cu1-N4 catalyst shows great promise for practical engineering applications in nitrate reduction.
• This approach facilitates the large-scale production of efficient single-atom catalysts.