Study on electrochemical oxidation behaviors and the diffusion mechanism of hydroquinone at pre-anodized carbon paste electrode by cyclic voltammetry

Ma, Linjin; Wang, Zhenhui; Li, Quanmin

doi:10.1039/c1an15865a

Cited by 12 publications

(6 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sensitivity obtained for pH 4 was higher than that obtained for others pH values ( Figure 3B) and therefore pH 4 was used for subsequent studies. [52,53] Incorporation of GQD at electrode surface was performed by cyclic voltammetry as suggest in literature [32,54], reduced graphene species are formed on the electrode surface by electrochemical measurements, that is, the p-p network conjugated bonds are restored with decrease of oxygenated groups amounts on carbonaceous surface, and the tuning of reduced graphene formed can be performed from by the modification of some experimental parameter. In this case, the electrodeposition step promotes reduced species formation and the number of voltammetric cycles is the parameter that will directly influence the degree of reduction, i. e. higher number of cycles greater reduction degree of GQD.…”

Section: Ph Influence and Reduction Degree Of Gqdsmentioning

confidence: 99%

Graphene Quantum Dots Modified Screen‐printed Electrodes as Electroanalytical Sensing Platform for Diethylstilbestrol

et al. 2019

View full text Add to dashboard Cite

In present work a simple methodology for electroanalytical sensing of diethylstilbestrol (DES) using graphene quantum dots (GQD) surface modified screen‐printed electrodes (SPE) is reported. GQD was synthesized by simple bottom‐up method based on citric acid pyrolysis at 200 °C and electrodeposited directly at electrode surface under cyclic voltammetric conditions. The obtained GQD presented an average diameter of 7 nm and was characterized by techniques such as transmission and scanning electron microscopy, and electrochemical impedance spectroscopy. The proposed sensor exhibits a linear response from 0.05 to 7.5 μmol L−1, with limit of detection and quantification of 8.8 nmol L−1 and 29.0 nmol L−1, respectively. The repeatability study presented RSD=3.6 % for 6 consecutive measurements using the same electrode surface and the reproducibility study showed RSD=6.6 % for measurements with 6 different electrode surfaces. The proposed sensor was successfully applied for DES determination in synthetic urine and tap water spiked samples and good recoveries were obtained without any sample pre‐treatment, showing its promising analytical performance.

show abstract

Section: Ph Influence and Reduction Degree Of Gqdsmentioning

confidence: 99%

Graphene Quantum Dots Modified Screen‐printed Electrodes as Electroanalytical Sensing Platform for Diethylstilbestrol

et al. 2019

View full text Add to dashboard Cite

show abstract

“…However, a clear difference was observed with PEDOT/PSS/LuPc 2 electrodes where a strong decrease in the oxidation peak voltage was not observed [33]. …”

Section: Resultsmentioning

confidence: 99%

Layered composites of PEDOT/PSS/nanoparticles and PEDOT/PSS/phthalocyanines as electron mediators for sensors and biosensors

García-Hernández¹,

Garcı́a²,

Martín-Pedrosa³

et al. 2016

Beilstein J. Nanotechnol.

View full text Add to dashboard Cite

The sensing properties of electrodes chemically modified with PEDOT/PSS towards catechol and hydroquinone sensing have been successfully improved by combining layers of PEDOT/PSS with layers of a secondary electrocatalytic material such as gold nanoparticles (PEDOT/PSS/AuNPs), copper phthalocyanine (PEDOT/PSS/CuPc) or lutetium bisphthalocyanine (PEDOT/PSS/LuPc2). Layered composites exhibit synergistic effects that strongly enhance the electrocatalytic activity as indicated by the increase in intensity and the shift of the redox peaks to lower potentials. A remarkable improvement has been achieved using PEDOT/PSS/LuPc2, which exhibits excellent electrocatalytic activity towards the oxidation of catechol. The kinetic studies demonstrated diffusion-controlled processes at the electrode surfaces. The kinetic parameters such as Tafel slopes and charge transfer coefficient (α) confirm the improved electrocatalytic activity of the layered electron mediators. The peak currents increased linearly with concentration of catechol and hydroquinone over the range of 1.5 × 10−4 to 4.0 × 10−6 mol·L−1 with a limit of detection on the scale of μmol·L−1. The layered composite hybrid systems were also found to be excellent electron mediators in biosensors containing tyrosinase and laccase, and they combine the recognition and biocatalytic properties of biomolecules with the unique catalytic features of composite materials. The observed increase in the intensity of the responses allowed detection limits of 1 × 10−7 mol·L−1 to be attained.

show abstract

“…The peak separation for the four molecules ranged from 380 to 608 mV, way beyond the theoretical expectation. This phenomenon was assigned to the low kinetics on the glassy carbon electrode [32].…”

Section: Reversibility and Redox Potentialmentioning

confidence: 99%

Novel, Stable Catholyte for Aqueous Organic Redox Flow Batteries: Symmetric Cell Study of Hydroquinones with High Accessible Capacity

et al. 2021

View full text Add to dashboard Cite

Owing to their broad range of redox potential, quinones/hydroquinones can be utilized for energy storage in redox flow batteries. In terms of stability, organic catholytes are more challenging than anolytes. The two-electron transfer feature adds value when building all-quinone flow battery systems. However, the dimerization of quinones/hydroquinones usually makes it difficult to achieve a full two-electron transfer in practical redox flow battery applications. In this work, we designed and synthesized four new hydroquinone derivatives bearing morpholinomethylene and/or methyl groups in different positions on the benzene ring to probe molecular stability upon battery cycling. The redox potential of the four molecules were investigated, followed by long-term stability tests using different supporting electrolytes and cell cycling methods in a symmetric flow cell. The derivative with two unoccupied ortho positions was found highly unstable, the cell of which exhibited a capacity decay rate of ~50% per day. Fully substituted hydroquinones turned out to be more stable. In particular, 2,6-dimethyl-3,5-bis(morpholinomethylene)benzene-1,4-diol (asym-O-5) displayed a capacity decay of only 0.45%/day with four-week potentiostatic cycling at 0.1 M in 1 M H3PO4. In addition, the three fully substituted hydroquinones displayed good accessible capacity of over 82%, much higher than those of conventional quinone derivatives.

show abstract

Study on electrochemical oxidation behaviors and the diffusion mechanism of hydroquinone at pre-anodized carbon paste electrode by cyclic voltammetry

Cited by 12 publications

References 17 publications

Graphene Quantum Dots Modified Screen‐printed Electrodes as Electroanalytical Sensing Platform for Diethylstilbestrol

Graphene Quantum Dots Modified Screen‐printed Electrodes as Electroanalytical Sensing Platform for Diethylstilbestrol

Layered composites of PEDOT/PSS/nanoparticles and PEDOT/PSS/phthalocyanines as electron mediators for sensors and biosensors

Novel, Stable Catholyte for Aqueous Organic Redox Flow Batteries: Symmetric Cell Study of Hydroquinones with High Accessible Capacity

Contact Info

Product

Resources

About