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Nb-doped NiO nanoflowers for nitrite electroreduction to ammonia.

ABSTRACT: Electrocatalytic reduction of nitrite to ammonia (NO₂RR) is considered as an appealing route to simultaneously achieve sustainable ammonia production and abate hazardous nitrite pollution. Herein, atomically Nb-doped NiO nanoflowers are designed as a high-performance NO₂RR catalyst, which exhibits the highest NH₃-Faradaic efficiency of 92.4% with an NH₃ yield rate of 200.5 μmol h^-1 cm^-2 at -0.6 V RHE. Theoretical calculations unravel that Nb dopants can act as Lewis acid sites to render effective NO₂^- activation, decreased protonation energy barriers, and restricted hydrogen evolution, ultimately leading to a high NO₂RR selectivity and activity.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC10558769 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Nb-doped NiO nanoflowers for nitrite electroreduction to ammonia.

Zhang Ying Y Wan Yuying Y Liu Xiaoxu X Chen Kai K Chu Ke K

iScience 20230919 10

Electrocatalytic reduction of nitrite to ammonia (NO2RR) is considered as an appealing route to simultaneously achieve sustainable ammonia production and abate hazardous nitrite pollution. Herein, atomically Nb-doped NiO nanoflowers are designed as a high-performance NO2RR catalyst, which exhibits the highest NH3-Faradaic efficiency of 92.4% with an NH3 yield rate of 200.5 μmol h-1 cm-2 at -0.6 V RHE. Theoretical calculations unra ...[more]

PMID: 37810221

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