Co-utilization of wastewater sludge and heavy metals for single-atom electrocatalytic reduction of gaseous CO2.
iScience
; 27(6): 109956, 2024 Jun 21.
Article
em En
| MEDLINE
| ID: mdl-38812555
ABSTRACT
Synergetic management of waste activated sludge, heavy metals (HMs) and CO2 for their valorization and cyclic utilization is rarely reported. Herein, we employed sludge-derived extracellular polymeric substances (EPS) and HMs in wastewater to fabricate a gas diffusion electrode (GDE) for electrochemical CO2 reduction. This approach atomically dispersed Ni at each nanofiber of the GDE. Abundant N element in the EPS proved to play a key role in the formation of Nx-Ni (mixture of N3-Ni and N4-Ni) sites for highly efficient CO2 to CO conversion. The atomical Ni3+ shows high catalytic activity. Direct gaseous CO2 reduction in a membrane electrode assembly generated a current density up to 50 mA·cm-2 with COH2 ratio of â¼100 and â¼75% FECO under 2.69 cell voltage. This strategy takes advantage of all waste streams generated on site and consolidates traditionally separated treatment processes to save costs, produces value-added products and generates carbon benefits during wastewater treatment.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article