Electrochemical behavior of methylene blue at bare and DNA-modified silver solid amalgam electrodes

Journal of Solid State Electrochemistry - Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used for a voltammetric study of methylene blue (MB) at a mercury meniscus-modified...     

Determination of 5-nitroindazole using silver solid amalgam electrode

Monatshefte für Chemie - Chemical Monthly - The voltammetric behavior of 5-nitroindazole was investigated at polished (p-AgSAE) and at mercury meniscus-modified (m-AgSAE) silver solid amalgam...     

The Role of Alkali Cation Intercalates on the Electrochemical Characteristics of Nb2CTX MXene for Energy Storage

The intercalation of cations into layered-structure electrode materials has long been studied in depth for energy storage applications. In particular, Li⁺-, Na⁺-, and K⁺-based cation transport in energy storage devices such as batteries and electrochemical capacitors is closely related to the capacitance behavior. We have exploited different sizes of cations from aqueous salt electrolytes intercalating into a layered Nb₂CT_x electrode in a supercapacitor for the first time. As a result, we have demonstrated that capacitive performance was dependent on cation intercalation behavior. The interlayer spacing expansion of the electrode material can be observed in Li₂SO₄, Na₂SO₄, and K₂SO₄ electrolytes with d-spacing. Additionally, our results showed that the Nb₂CT_x electrode exhibited higher electrochemical performance in the presence of Li₂SO₄ than in that of Na₂SO₄ and K₂SO₄. This is partly because the smaller-sized Li⁺ transports quickly and intercalates between the layers of Nb₂CT_x easily. Poor ion transport in the Na₂SO₄ electrolyte limited the electrode capacitance and presented the lowest electrochemical performance, although the cation radius follows Li⁺>Na⁺>K⁺. Our experimental studies provide direct evidence for the intercalation mechanism of Li⁺, Na⁺, and K⁺ on the 2D layered Nb₂CT_x electrode, which provides a new path for exploring the relationship between intercalated cations and other MXene electrodes.     

Polyelectrolyte multilayers as stationary phases for open tubular ion chromatography

Polyelectrolyte multilayers deposited on the wall of fused silica capillaries were used as stationary phases in open tubular ion chromatography. The multilayers were formed by flushing the capillaries with solutions of polyanions and polycations such as polydiallyldimethylammonium chloride and dextran sulphate. Columns with several bi-layers were constructed and used in low pressure non-suppressed open tubular ion chromatography of common inorganic anions (F⁻, Cl⁻, NO₃⁻) and cations (Li⁺, Na⁺, NH₄⁺, K⁺, Cs⁺) with contactless conductometric detection. Using sodium benzoate and tartaric acid eluents the separations were typically achieved in less than 35 min with separation efficiencies between 2000 and 9000 theoretical plates. A bi-functional column was prepared that contains both anionic and cationic functional groups and was used for simultaneous separation of anions and cations.