The Electrochemical Impedance of Porous Nickel Electrodes in Alkaline Media: II . Nonuniform Transmission Line Analysis

1991 ◽  
Vol 138 (5) ◽  
pp. 1359-1363 ◽  
Author(s):  
D. D. Macdonald ◽  
M. Urquidi‐Macdonald ◽  
S. D. Bhakta ◽  
B. G. Pound
1991 ◽  
Vol 138 (5) ◽  
pp. 1353-1358 ◽  
Author(s):  
S. D. Bhakta ◽  
D. D. Macdonald ◽  
B. G. Pound ◽  
M. Urquidi‐Macdonald

Catalysts ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 453 ◽  
Author(s):  
Laura Mais ◽  
Simonetta Palmas ◽  
Michele Mascia ◽  
Elisa Sechi ◽  
Maria Francesca Casula ◽  
...  

In this work, a dealloying technique is proposed as a synthesis method to obtain highly porous Nickel electrodes starting from Ni-Cu co-deposit: pulsed corrosion is applied adopting different corrosion and relaxation times. Different morphologies, pore size distribution and residual copper amount were obtained depending on the corrosion conditions. For the developed electrodes, the surface roughness factor, Rf, was evaluated by electrochemical impedance spectroscopy (EIS). The hydrogen evolution reaction (HER) on these electrodes was evaluated by means of steady-state polarization curves, and the related parameters were derived by Tafel analysis. Finally, a thin layer of NiO on the porous structures was obtained to exploit the semiconductor characteristic of the oxide, so that an extra-photopotential was obtained by the simulated solar light action. Results demonstrate greater apparent activity of the developed electrodes towards HER in comparison with commercial smooth Ni electrode, which can be mainly attributed to the large Rf obtained with the proposed technique.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Magdalena Warczak ◽  
Marianna Gniadek ◽  
Kamil Hermanowski ◽  
Magdalena Osial

Abstract Over the recent decades, conducting polymers have received great interest in many fields including microelectronics, energy conversion devices, and biosensing due to their unique properties like electrical conductivity, stability, and simple synthesis. Modification of conducting polymers with noble metals e.g. gold enhances their properties and opens new opportunities to also apply them in other fields like electrocatalysis. Here, we focus on the synthesis of hybrid material based on polyindole (PIN) nanobrush modified with gold nanoparticles and its application towards electrooxidation of ethanol. The paper presents systematic studies from synthesis to electrochemical sensing applications. For the characterization of PIN–Au composites, scanning electron microscopy and X-ray diffraction analyses were used. The electrocatalytic performance of the proposed hybrid material towards alcohol oxidation was studied in alkaline media by cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy techniques. The results show that PIN–Au hybrid can be employed as an effective and sensitive platform for the detection of alcohols, which makes it a promising material in electrocatalysis or sensors. Moreover, the proposed composite exhibits electrocatalytic activity towards ethanol oxidation, which combined with its good long-term stability opens the opportunity for its application in fuel cells.


2016 ◽  
Vol 65 ◽  
pp. 93-102 ◽  
Author(s):  
Salvatore Campione ◽  
Lorena I. Basilio ◽  
Larry Kevin Warne ◽  
Howard Gerald Hudson ◽  
William L. Langston

2015 ◽  
Vol 83 (5) ◽  
pp. 335-338 ◽  
Author(s):  
Isao SHITANDA ◽  
Seiya TSUJIMURA ◽  
Hiroki YANAI ◽  
Yoshinao HOSHI ◽  
Masayuki ITAGAKI

2021 ◽  
Vol 21 (4) ◽  
pp. 2660-2667
Author(s):  
Abdul Qayoom Mugheri ◽  
Aneela Tahira ◽  
Umair Aftab ◽  
Adeel Liaquat Bhatti ◽  
Ramesh Lal ◽  
...  

Cobalt oxide has been widely investigated among potential transition metal oxides for the electrochemical energy conversion, storage, and water splitting. However, they have inherently low electronic conductivity and high corrosive nature in alkaline media. Herein, we propose a promising and facile approach to improve the conductivity and charge transport of cobalt oxide Co3O4 through chemical coupling with well-dispersed multiwall carbon nanotubes (MWCNTs) during hydrothermal treatment. The morphology of prepared composite material consisting of nanosheets which are anchored on the MWCNTs as confirmed by scanning electron microscopy (SEM). A cubic crystalline system is exhibited by the cobalt oxide as confirmed by the X-ray diffraction study. The Co, O, and C are the only elements present in the composite material. FTIR study has indicated the successful coupling of cobalt oxide with MWCNTs. The chemically coupled cobalt oxide onto the surface of MWCNTs composite is found highly active towards oxygen evolution reaction (OER) with a low onset potential 1.44 V versus RHE, low overpotential 262 mV at 10 mAcm-2 and small Tafel slope 81 mV dec-1. For continuous operation of 40 hours during durability test, no decay in activity was recorded. Electrochemical impedance study further revealed a low charge transfer resistance of 70.64 Ohms for the composite material during the electrochemical reaction and which strongly favored OER kinetics. This work provides a simple, low cost, and smartly designing electrocatalysts via hydrothermal reaction for the catalysis and energy storage applications.


2020 ◽  
Vol 14 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Anthony C. Boucouvalas ◽  
Christos Papageorgiou ◽  
Euripides Georgantzos

Sign in / Sign up

Export Citation Format

Share Document