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Efficient electrocatalyst of α-Fe₂O₃ nanorings for oxygen evolution reaction in acidic conditions.

ABSTRACT: Large-scale application of sustainable energy devices urgently requires cost-effective electrocatalysts to overcome the sluggish kinetics related to the oxygen evolution reaction (OER) under acidic conditions. Here, we first report the highly efficient electrocatalytic characteristics of α-Fe₂O₃ nanorings (NRs), which exhibits prominent OER electrocatalytic activity with lower overpotential of 1.43 V at 10 mA cm^-2 and great stability in 1 M HCl, surpassing the start-of-the art Ir/C electrocatalyst. The significantly optimized OER activity of the α-Fe₂O₃ NRs mainly attributes to the synergistic effect of the excellent electrical conductivity and a large effective active surface because of their unique nanoring structure, disordered surface, and the dynamic stability of α-Fe₂O₃ NRs in acidic conditions.

SUBMITTER: Liang X

PROVIDER: S-EPMC9055951 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Efficient electrocatalyst of α-Fe2O3 nanorings for oxygen evolution reaction in acidic conditions.

Liang Xiaolei X Qian Jinmei J Liu Yonggang Y Zhang Zhengmei Z Gao Daqiang D

RSC advances 20200806 49

Large-scale application of sustainable energy devices urgently requires cost-effective electrocatalysts to overcome the sluggish kinetics related to the oxygen evolution reaction (OER) under acidic conditions. Here, we first report the highly efficient electrocatalytic characteristics of α-Fe2O3 nanorings (NRs), which exhibits prominent OER electrocatalytic activity with lower overpotential of 1.43 V at 10 mA cm-2 and great stability in 1 M HCl, surpassing the st ...[more]

PMID: 35521123

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