Highly Efficient Hydroxyl Radicals Production Boosted by the Atomically Dispersed Fe and Co Sites for Heterogeneous Electro-Fenton Oxidation.
Environ Sci Technol
; 57(7): 2907-2917, 2023 02 21.
Article
em En
| MEDLINE
| ID: mdl-36749299
ABSTRACT
The heterogeneous electro-Fenton (hetero-e-Fenton)-coupled electrocatalytic oxygen reduction reaction (ORR) is regarded as a promising strategy for ·OH production by simultaneously driving two-electron ORR toward H2O2 and stepped activating the as-generated H2O2 to ·OH. However, the high-efficiency electrogeneration of ·OH remains challengeable, as it is difficult to synchronously obtain efficient catalysis of both reaction steps above on one catalytic site. In this work, we propose a dual-atomic-site catalyst (CoFe DAC) to cooperatively catalyze ·OH electrogeneration, where the atomically dispersed Co sites are assigned to enhance O2 reduction to H2O2 intermediates and Fe sites are responsible for activation of the as-generated H2O2 to ·OH. The CoFe DAC delivers a higher ·OH production rate of 2.4 mmol L-1 min-1 gcat-1 than the single-site catalyst Co-NC (0.8 mmol L-1 min-1 gcat-1) and Fe-NC (1.0 mmol L-1 min-1 gcat-1). Significantly, the CoFe DAC hetero-e-Fenton process is demonstrated to be more energy-efficient for actual coking wastewater treatment with an energy consumption of 19.0 kWh kg-1 COD-1 than other electrochemical technologies that reported values of 29.7â¼68.0 kW h kg-1 COD-1. This study shows the attractive advantages of efficiency and sustainability for ·OH electrogeneration, which should have fresh inspiration for the development of new-generation wastewater treatment technology.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
/
Purificação da Água
Idioma:
En
Revista:
Environ Sci Technol
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
China