Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media

Ligands play a critical role in the electrocatalytic CO2 reduction reaction (CO2RR) based on heterogeneous molecular catalysts. Previous research on heterogeneous molecular electrocatalysis has mainly dealt with N4 ligands with pyrrole as subunits (porphyrin, phthalocyanine, etc.), while ligands con...

Full description

Saved in:
Bibliographic Details
Main Authors: Sun, Libo, Reddu, Vikas, Xi, Shibo, Dai, Chencheng, Sheng, Yuan, Su, Tan, Fisher, Adrian C., Wang, Xin
Other Authors: School of Chemical and Biomedical Engineering
Format: Article
Language:English
Published: 2022
Subjects:
Online Access:https://hdl.handle.net/10356/163471
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
Language: English
id sg-ntu-dr.10356-163471
record_format dspace
spelling sg-ntu-dr.10356-1634712022-12-07T04:39:57Z Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media Sun, Libo Reddu, Vikas Xi, Shibo Dai, Chencheng Sheng, Yuan Su, Tan Fisher, Adrian C. Wang, Xin School of Chemical and Biomedical Engineering School of Materials Science and Engineering Cambridge Centre for Advanced Research and Education in Singapore Ltd Engineering::Chemical engineering Heterogeneous Electrocatalysis Heterogeneous Molecular Catalysts Ligands play a critical role in the electrocatalytic CO2 reduction reaction (CO2RR) based on heterogeneous molecular catalysts. Previous research on heterogeneous molecular electrocatalysis has mainly dealt with N4 ligands with pyrrole as subunits (porphyrin, phthalocyanine, etc.), while ligands constructed from pyridine subunits remain uncommon. The examples for comparing active configurations are few and far between. Herein, the development of new N4 cobalt complexes based on pyridine subunits is explored. After anchoring onto carbon nanotubes, they can exhibit CO2RR activity at a low overpotential of 140 mV, and high activity from -0.30 to -0.60 V versus reference hydrogen electrode with a selectivity of above 98%. Excellent performance at large current densities can also be observed in a flow cell. In situ attenuated total reflectance-Fourier transform infrared spectroscopy proves that such electrocatalysts exhibit CO production at lower overpotential and moderate CO adsorption ability over a wide potential range. From density functional theory calculations, it is shown that a pyridine-based cobalt complex on a carbon substrate can reduce the Gibbs free energy for reactions further than its counterpart pyrrole-based ones. Further analysis proves that the semimetal behavior of optimized d-orbitals may facilitate charge transfer and increase the activity. This provides a new insight for understanding catalytically active moieties in heterogeneous molecular catalysts with ligands constructed from pyridine subunits. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) National Research Foundation (NRF) This project was supported by the National Research Foundation (NRF), Prime Minister’s Office, Singapore, under its Campus for Research Excellence and Technological Enterprise (CREATE) program. The authors also acknowledge financial support from the academic research fund AcRF tier 1 (M4012076 RG118/18), Ministry of Education, Singapore, AME Individual Research Grant (Grant number: A1983c0026), Agency for Science, Technology, and Research (A*STAR), Singapore. 2022-12-07T04:39:57Z 2022-12-07T04:39:57Z 2022 Journal Article Sun, L., Reddu, V., Xi, S., Dai, C., Sheng, Y., Su, T., Fisher, A. C. & Wang, X. (2022). Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media. Advanced Energy Materials, 12(34), 2202108-. https://dx.doi.org/10.1002/aenm.202202108 1614-6832 https://hdl.handle.net/10356/163471 10.1002/aenm.202202108 2-s2.0-85134528841 34 12 2202108 en M4012076 RG118/1 A1983c0026 Advanced Energy Materials © 2022 Wiley-VCH GmbH. All rights reserved.
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic Engineering::Chemical engineering
Heterogeneous Electrocatalysis
Heterogeneous Molecular Catalysts
spellingShingle Engineering::Chemical engineering
Heterogeneous Electrocatalysis
Heterogeneous Molecular Catalysts
Sun, Libo
Reddu, Vikas
Xi, Shibo
Dai, Chencheng
Sheng, Yuan
Su, Tan
Fisher, Adrian C.
Wang, Xin
Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
description Ligands play a critical role in the electrocatalytic CO2 reduction reaction (CO2RR) based on heterogeneous molecular catalysts. Previous research on heterogeneous molecular electrocatalysis has mainly dealt with N4 ligands with pyrrole as subunits (porphyrin, phthalocyanine, etc.), while ligands constructed from pyridine subunits remain uncommon. The examples for comparing active configurations are few and far between. Herein, the development of new N4 cobalt complexes based on pyridine subunits is explored. After anchoring onto carbon nanotubes, they can exhibit CO2RR activity at a low overpotential of 140 mV, and high activity from -0.30 to -0.60 V versus reference hydrogen electrode with a selectivity of above 98%. Excellent performance at large current densities can also be observed in a flow cell. In situ attenuated total reflectance-Fourier transform infrared spectroscopy proves that such electrocatalysts exhibit CO production at lower overpotential and moderate CO adsorption ability over a wide potential range. From density functional theory calculations, it is shown that a pyridine-based cobalt complex on a carbon substrate can reduce the Gibbs free energy for reactions further than its counterpart pyrrole-based ones. Further analysis proves that the semimetal behavior of optimized d-orbitals may facilitate charge transfer and increase the activity. This provides a new insight for understanding catalytically active moieties in heterogeneous molecular catalysts with ligands constructed from pyridine subunits.
author2 School of Chemical and Biomedical Engineering
author_facet School of Chemical and Biomedical Engineering
Sun, Libo
Reddu, Vikas
Xi, Shibo
Dai, Chencheng
Sheng, Yuan
Su, Tan
Fisher, Adrian C.
Wang, Xin
format Article
author Sun, Libo
Reddu, Vikas
Xi, Shibo
Dai, Chencheng
Sheng, Yuan
Su, Tan
Fisher, Adrian C.
Wang, Xin
author_sort Sun, Libo
title Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
title_short Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
title_full Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
title_fullStr Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
title_full_unstemmed Cobalt quaterpyridine complexes for highly efficient heterogeneous CO₂ reduction in aqueous media
title_sort cobalt quaterpyridine complexes for highly efficient heterogeneous co₂ reduction in aqueous media
publishDate 2022
url https://hdl.handle.net/10356/163471
_version_ 1753801079952244736