Lowering the Cu-O bond energy in CuO nanocatalysts enhances the efficiency of NH<sub>3</sub> oxidation.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41136373.
- Also identified by DOI 10.1038/s41467-025-64415-w and PMC identifier 12552456.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Tuning the electronic properties of nanocatalysts via doping with monodispersed hetero-metal atoms is an effective method used to enhance catalytic properties. Doping CuO nanoparticles with monodispersed Co atoms using different reductants affords catalysts (Co<sub>B</sub>Cu/Al<sub>2</sub>O<sub>3</sub> and Co<sub>H</sub>Cu/Al<sub>2</sub>O<sub>3</sub>) with strikingly different electronic structures. Compared to Co<sub>H</sub>Cu/Al<sub>2</sub>O<sub>3</sub>, the CuO nanoparticles in Co<sub>B</sub>Cu/Al<sub>2</sub>O<sub>3</sub> have longer and weaker Cu-O bonds, with a lower 1s → 4p<sub>z</sub> antibonding transition and higher 4p → 1s bonding transition (as demonstrated from HERFD-XANES and valence-to-core X-ray emission spectroscopy). The weaker Cu-O bonds in Co<sub>B</sub>Cu/Al<sub>2</sub>O<sub>3</sub> lead to superior redox activity of the CuO nanoparticles, evidenced from operando XAFS and in-situ near ambient pressure-near edge X-ray absorption fine structures studies. Such superior redox properties of CuO in Co<sub>B</sub>Cu/Al<sub>2</sub>O<sub>3</sub> result in a much reduced activation energy of Co<sub>B</sub>Cu/Al<sub>2</sub>O<sub>3</sub> compared to Co<sub>H</sub>Cu/Al<sub>2</sub>O<sub>3</sub> (40.0 vs. 63.5 kJ/mol), thus leading to an enhancement in catalytic performance in the selective catalytic oxidation of NH<sub>3</sub> to N<sub>2</sub>.