Tuning Nitrate Electroreduction Activity via an Equilibrium Adsorption Strategy: A Computational Study
Lei Yang1, Shenghua Feng1, Weihua Zhu1
1Institute for Computation in Molecular and Materials Science, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
The Journal of Physical Chemistry Letters
|February 14, 2022
Summary
Researchers developed new catalysts for converting nitrates into valuable chemicals, improving environmental sustainability. Hafnium anchored on g-C3N4 (Hf/g-C3N4) showed exceptional performance in the electrochemical nitrate reduction reaction (NO3RR).
Area of Science:
- Materials Science
- Electrochemistry
- Environmental Chemistry
Background:
- Nitrate pollution poses environmental risks.
- Converting nitrates to industrial chemicals offers sustainability benefits.
- Electrochemical nitrate reduction reaction (NO3RR) is a promising technology.
Purpose of the Study:
- To evaluate transition metal (TM) anchored g-C3N4 (TM/g-C3N4) catalysts for NO3RR.
- To identify high-performance electrocatalysts for nitrate conversion.
- To explore the application of electrocatalysis in treating explosive-contaminated wastewater.
Main Methods:
- Density functional theory (DFT) calculations.
- Ab initio molecular dynamics simulations.
- Development of a novel equilibrium adsorption model for catalyst screening.
- High-throughput calculations.
Main Results:
- Hf/g-C3N4 demonstrated remarkable NO3RR activity with a limiting potential of 0.11 V.
- Superior electrode selectivity suppressed byproduct formation and accelerated the reaction.
- Electronic structure analysis revealed the catalytic activity origins, highlighting IVB group elements.
- Stability of the catalysts was confirmed through formation energy and molecular dynamics simulations.
Conclusions:
- Hf/g-C3N4 is a highly promising electrocatalyst for the nitrate reduction reaction.
- This study provides high-performance electrode candidates for environmental applications.
- The work establishes a precedent for using electrocatalysis in treating explosive-contaminated wastewater.
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