Tunable Syngas Production through CO2 Electroreduction on Cobalt-Carbon Composite Electrocatalyst

Rahman Daiyan; Rui Chen; Priyank Kumar; Nicholas M Bedford; Jiangtao Qu; Julie M Cairney; Xunyu Lu; Rose Amal

doi:10.1021/acsami.9b21216

Tunable Syngas Production through CO₂ Electroreduction on Cobalt-Carbon Composite Electrocatalyst

ACS Appl Mater Interfaces. 2020 Feb 26;12(8):9307-9315. doi: 10.1021/acsami.9b21216. Epub 2020 Feb 14.

Authors

Rahman Daiyan¹, Rui Chen¹, Priyank Kumar¹, Nicholas M Bedford¹, Jiangtao Qu^{2

3}, Julie M Cairney^{2

3}, Xunyu Lu¹, Rose Amal¹

Affiliations

¹ Particles and Catalysis Research Laboratory, School of Chemical Engineering , The University of New South Wales , Sydney , New South Wales 2052 , Australia.
² Aerospace, Mechanical and Mechatronic Engineering , The University of Sydney , Sydney , New South Wales 2006 , Australia.
³ Australian Centre for Microscopy and Microanalysis , The University of Sydney , Sydney , New South Wales 2006 , Australia.

PMID: 32023413
DOI: 10.1021/acsami.9b21216

Abstract

Controllable concomitant production of CO and H₂ (syngas) during electrochemical CO₂ reduction reactions (CO₂RR) is expected to improve the commercial feasibility of the technology to mitigate CO₂ emissions as the generated syngas can be converted into useful chemicals using the commercial Fischer-Tropsch (FT) process. Herein, we demonstrate the ability of a Co single-atom-decorated N-doped graphitic carbon shell-encapsulated cobalt nanoparticle electrocatalyst (referred as Co@CoNC-900) to controllably produce syngas at low overpotentials during CO₂RR. Through the engineering and modulation of dual active sites for CO₂RR (modified carbon shell with encapsulated Co) and hydrogen evolution reaction (Co-N₄ moieties) within Co@CoNC by varying the annealing temperature, we are able to tune the H₂: CO ratio from 1: 2 to 1: 1 to 3: 2 over a wide range of applied potentials (-0.5 V to -0.8 V versus reversible hydrogen electrode, RHE). This versatile control of H₂: CO ratio in CO₂RR reaction brings up significant opportunity of using CO₂ and H₂O and renewable energy for producing a range of chemicals.

Keywords: CO2 reduction; Co−N4; cobalt nanoparticles; graphitic carbon shell; hydrogen evolution reaction; single atoms.