Advanced search
1 file | 1.46 MB Add to list

Homogenous electrochemical water oxidation by a nickel(II) complex based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand

(2019) CATALYSIS SCIENCE & TECHNOLOGY. 9(20). p.5651-5659
Author
Organization
Abstract
Water-soluble homogeneous nickel catalysts have been rarely investigated for catalytic water oxidation as compared to their heterogeneous counterparts. Herein, we report homogenous electrochemical water oxidation by a nickel(ii) complex, ([NiL](PF6)(2) (L = bis(2-pyridyl-methylimidazolylidene)methane), based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand under neutral and alkaline conditions. The catalyst displayed the stable catalytic current of 0.65 mA cm(-2) at the overpotential of 0.80 V (similar to 0.55 V at GCE for CV) with a similar to 93% Faradaic efficiency at pH 9.0 for oxygen evolution in long-term bulk electrolysis. The CV, UV-vis, ESI-MS, SEM, and EDX results demonstrated that the catalyst was impressively stable even after long-term controlled potential electrolysis (CPE) (11 h) and homogeneous in nature. The synthesis of this catalyst is straightforward, and its complex is air and moisture stable. To the best of our knowledge, this is the first study on the investigation of a Ni-NHC complex for water oxidation under aqueous conditions (acetate/phosphate). According to the literature, the role of the phosphate ion in homogenous nickel-catalysed water oxidation was found to vary from catalyst poisoning to activation. Interestingly, the catalytic activity of our catalyst in phosphate buffer was significantly higher than that with acetate ions at the same pH value; this might indicate the key role of phosphate ions as proton acceptors, which boosted the catalyst activity via enhanced PCET during catalysis.
Keywords
OXYGEN EVOLUTION REACTION, HIGHLY EFFICIENT, METAL-COMPLEXES, NEUTRAL PH, IN-SITU, STRUCTURAL-CHARACTERIZATION, IRIDIUM COMPLEXES, ELECTRON-TRANSFER, RECENT PROGRESS, CATALYSTS

Downloads

  • (...).pdf
    • full text
    • |
    • UGent only
    • |
    • PDF
    • |
    • 1.46 MB

Citation

Please use this url to cite or link to this publication:

MLA
Shahadat, Hossain M., et al. “Homogenous Electrochemical Water Oxidation by a Nickel(II) Complex Based on a Macrocyclic N-Heterocyclic Carbene/Pyridine Hybrid Ligand.” CATALYSIS SCIENCE & TECHNOLOGY, vol. 9, no. 20, 2019, pp. 5651–59.
APA
Shahadat, H. M., Younus, H. A., Ahmad, N., Rahaman, M. A., Khattak, Z. A., Zhuiykov, S., & Verpoort, F. (2019). Homogenous electrochemical water oxidation by a nickel(II) complex based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand. CATALYSIS SCIENCE & TECHNOLOGY, 9(20), 5651–5659.
Chicago author-date
Shahadat, Hossain M, Hussein A Younus, Nazir Ahmad, Md Abdur Rahaman, Zafar AK Khattak, Serge Zhuiykov, and Francis Verpoort. 2019. “Homogenous Electrochemical Water Oxidation by a Nickel(II) Complex Based on a Macrocyclic N-Heterocyclic Carbene/Pyridine Hybrid Ligand.” CATALYSIS SCIENCE & TECHNOLOGY 9 (20): 5651–59.
Chicago author-date (all authors)
Shahadat, Hossain M, Hussein A Younus, Nazir Ahmad, Md Abdur Rahaman, Zafar AK Khattak, Serge Zhuiykov, and Francis Verpoort. 2019. “Homogenous Electrochemical Water Oxidation by a Nickel(II) Complex Based on a Macrocyclic N-Heterocyclic Carbene/Pyridine Hybrid Ligand.” CATALYSIS SCIENCE & TECHNOLOGY 9 (20): 5651–5659.
Vancouver
1.
Shahadat HM, Younus HA, Ahmad N, Rahaman MA, Khattak ZA, Zhuiykov S, et al. Homogenous electrochemical water oxidation by a nickel(II) complex based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand. CATALYSIS SCIENCE & TECHNOLOGY. 2019;9(20):5651–9.
IEEE
[1]
H. M. Shahadat et al., “Homogenous electrochemical water oxidation by a nickel(II) complex based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand,” CATALYSIS SCIENCE & TECHNOLOGY, vol. 9, no. 20, pp. 5651–5659, 2019.
@article{8633748,
  abstract     = {Water-soluble homogeneous nickel catalysts have been rarely investigated for catalytic water oxidation as compared to their heterogeneous counterparts. Herein, we report homogenous electrochemical water oxidation by a nickel(ii) complex, ([NiL](PF6)(2) (L = bis(2-pyridyl-methylimidazolylidene)methane), based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand under neutral and alkaline conditions. The catalyst displayed the stable catalytic current of 0.65 mA cm(-2) at the overpotential of 0.80 V (similar to 0.55 V at GCE for CV) with a similar to 93% Faradaic efficiency at pH 9.0 for oxygen evolution in long-term bulk electrolysis. The CV, UV-vis, ESI-MS, SEM, and EDX results demonstrated that the catalyst was impressively stable even after long-term controlled potential electrolysis (CPE) (11 h) and homogeneous in nature. The synthesis of this catalyst is straightforward, and its complex is air and moisture stable. To the best of our knowledge, this is the first study on the investigation of a Ni-NHC complex for water oxidation under aqueous conditions (acetate/phosphate). According to the literature, the role of the phosphate ion in homogenous nickel-catalysed water oxidation was found to vary from catalyst poisoning to activation. Interestingly, the catalytic activity of our catalyst in phosphate buffer was significantly higher than that with acetate ions at the same pH value; this might indicate the key role of phosphate ions as proton acceptors, which boosted the catalyst activity via enhanced PCET during catalysis.},
  author       = {Shahadat, Hossain M and Younus, Hussein A and Ahmad, Nazir and Rahaman, Md Abdur and Khattak, Zafar AK and Zhuiykov, Serge and Verpoort, Francis},
  issn         = {2044-4753},
  journal      = {CATALYSIS SCIENCE & TECHNOLOGY},
  keywords     = {OXYGEN EVOLUTION REACTION,HIGHLY EFFICIENT,METAL-COMPLEXES,NEUTRAL PH,IN-SITU,STRUCTURAL-CHARACTERIZATION,IRIDIUM COMPLEXES,ELECTRON-TRANSFER,RECENT PROGRESS,CATALYSTS},
  language     = {eng},
  number       = {20},
  pages        = {5651--5659},
  title        = {Homogenous electrochemical water oxidation by a nickel(II) complex based on a macrocyclic N-heterocyclic carbene/pyridine hybrid ligand},
  url          = {http://dx.doi.org/10.1039/c9cy01485c},
  volume       = {9},
  year         = {2019},
}

Altmetric
View in Altmetric
Web of Science
Times cited: