Electrochemistry of methanofullerene films: Simultaneous cyclic voltammetry and electrochemical quartz crystal microbalance studies

The optical properties of palladium phthalocyanine in dimethylformamide, toluene, acetonitrile, and dichloromethane solutions were studied in the visible range of energy. Palladium phthalocyanine in organic medium presented itself as a mixture of monomeric and dimeric species in equilibrium, and it was only in dichloromethane that the monomeric, non-aggregated form predominated. Palladium phthalocyanine films were prepared by casting, and studied by cyclic voltammetry and spectroelectrochemistry. The films showed an electrochromic response from blue to purple, and stability that depended on the applied potential. Electrochemical quartz crystal microbalance experiments indicated that the film exfoliates into solution after applying high values of final potentials. Raman spectroscopy was used to structurally characterize the palladium phthalocyanine film, which showed a central metal with +2 oxidation state that is not affected even when the film is oxidized.

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Selenium(IV) Electrochemistry on Silver: A Combined Electrochemical Quartz-Crystal Microbalance and Cyclic Voltammetric Investigation

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20031579 ◽

2003 ◽

Vol 68 (9) ◽

pp. 1579-1595 ◽

Cited By ~ 14

Author(s):

Giovanni Pezzatini ◽

Francesca Loglio ◽

Massimo Innocenti ◽

Maria Luisa Foresti

Keyword(s):

Cyclic Voltammetry ◽

Quartz Crystal Microbalance ◽

Electrochemical Behavior ◽

Quartz Crystal ◽

Reduction Process ◽

Electrochemical Quartz Crystal Microbalance ◽

Potential Range ◽

Cyclic Voltammetric ◽

Scan Rate ◽

Process Of Se

The electrochemical behavior of Se(IV) on silver was investigated by cyclic voltammetry and electrochemical quartz-crystal microbalance (EQCM) measurements. As already reported in the literature, Se(IV) electrochemistry is always complex, and on silver even more, due to the formation of a compound. Our results confirm that the reduction process of Se(IV) occurs through two reaction paths, Se(IV) → Se(0) and Se(IV) → Se(-II); the product Se(-II) then reacts with Se(IV) through a comproportionation reaction. The latter step leads to red Se that, according to the literature, is the only electroactive form of Se(0). The presence of the electroactive red Se is evident both in the negative range of potentials, through the reduction Se(0) → Se(-II), and in the less negative range of potentials, through the oxidation Se(0) → Se(IV). Moreover, our measurements pointed to the formation of a deposit that never redissolves. This deposit seems to be the electroinactive gray Se. The electrochemical behavior of Se(IV) was investigated in the whole potential range accessible on silver. Our results confirm the occurrence of competitive processes whose predominance depends on the scan rate, as well as on the potential limits of voltammetry. A detailed table with the processes occurring in different potential ranges was drawn up.

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Investigation of Gold Electrosorption onto Gold and Carbon Electrodes using an Electrochemical Quartz Crystal Microbalance

Eurasian Chemico-Technological Journal ◽

10.18321/ectj885 ◽

2019 ◽

Vol 21 (4) ◽

pp. 283

Author(s):

Z. Mansurov ◽

Zh. Supiyeva ◽

Kh. Avchukir ◽

A. Taurbekov ◽

M. Yeleuov ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Quartz Crystal Microbalance ◽

Quartz Crystal ◽

Background Electrolyte ◽

Electrochemical Quartz Crystal Microbalance ◽

Carbon Surface ◽

Carbon Electrodes ◽

Electron Microscopic ◽

Sem Images ◽

Cyclic Voltammetry Method

The adsorption behavior of Au3+ ions on metal electrodes has been studied using an electrochemical quartz crystal microbalance combined with the cyclic voltammetry technique. The experiments were carried out for HAuCl4 using 0.1 mol·L-1 HCl (pH~1) as a background electrolyte solution. The kinetics of electroreduction of Au3+ ions on the rice husk based activated carbon and gold electrodes in chloride electrolytes by the cyclic voltammetry and the electrochemical quartz crystal microbalance with a variation of the scan rate in the range of 5‒50 mV·s-1 has been studied. The diffusion coefficient of Au3+ ions for the tested solution on gold and carbon electrodes was determined by the cyclic voltammetry method on the basis of the Randles-Ševčik equation. It is found that electroreduction of gold goes via the discharge of AuCl4- complexes to the formation of metallic gold with a current efficiency of 97‒99%. The scanning electron microscopic images of the gold adsorbed carbon surface was taken to see gold particles and their morphology. In SEM images, it is clearly seen that the surface of carbon has a relief structure and gold has grown in the form of clusters. The smallest gold nanoparticles that could be examined were 100‒250 nm in diameter on the surface of the c arbon electrode.

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