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The discovery of the glass electrode by Max Cremer was possible because of the advances made in the nineteenth century in understanding the electrical properties of glass, and because of the studies of electrical potential drops at the interface of phases. The discovery of the Leiden jar by E. G. von Kleist and the follow-up studies of the properties of that capacitor disclosed that glass is a dielectric. Much later, the ionic conductivity of glass was noticed and studied by J. H. Buff, W. von Beetz, W. Thomson (Baron Kelvin of Largs), W. Giese, H. L. F. von Helmholtz, E. Warburg, etc. It needed also the discovery of electromotive forces due to the partition of mobile ions (charge separation) by W. Nernst and E. H. Riesenfeld to pave the way for the idea that ion partition also occurs at solid–solution interfaces producing electromotive forces (emf). At the beginning of the twentieth century, the ground was laid to expect that a very thin glass membrane may produce an electromotive force because the glass has a finite ionic conductivity and ion partition may cause an emf. It obviously needed a physiologist like Max Cremer who desired to mimic a cell membrane (a semipermeable membrane), to use a glass membrane for that purpose. Cremer’s congenial choice of a thin glass bulb was rooted in a thorough understanding of the origin of electromotive forces, and it was not initiated directly by the Giese-Helmholtz cell, as some later reviews suggested. Later Cremer realized that an emf builds up when aqueous solutions are separated by a thin glass membrane. Cremer’s discovery was picked up by F. Haber who developed the glass electrode together with his PhD student Z. Klemensiewicz as an analytical tool. The following decades have brought improvements of the glasses and measuring techniques, and a deeper insight into the functioning of the glass electrode. Here, it will be shown that full credit for the discovery of the glass electrode effect must be given to Max Cremer. Unfortunately, his role has not been adequately described so far, mainly because Haber dominated the literature.

The electro-oxidation of methanol at supported tungsten carbide (WC) nanoparticles in sulfuric acid solution was studied using cyclic voltammetry, potentiostatic measurements, and differential electrochemical mass spectroscopy (DEMS). The catalyst was prepared by a sonochemical method and characterized by X-ray diffraction. Over the WC catalyst, the oxidation of methanol (1 M in a sulfuric acid electrolyte) begins at a potential below 0.5 V/RHE during the anodic sweep. During potentiostatic measurements, a maximum current of 0.8 mA mg−1 was obtained at 0.4 V. Measurements of DEMS showed that the methanol oxidation reaction over tungsten carbide produces CO2 (m/z = 44); no methylformate (m/z = 60) was detected. These results are discussed in the context of the continued search for alternative materials for the anode catalyst of direct methanol fuel cells.

In the present work, the conduction ions in 15NaI∙LiBH4 are investigated by secondary ion mass spectroscopy (SIMS) and galvanostatic measurements. An all-solid-state half-cell is constructed using 15NaI∙LiBH4 and a Sn film as the solid electrolyte and working electrode, respectively. SIMS depth profiles in a charged Sn film indicate that 7Li+ is the dominant charging ion, while the intensity of 23Na+ ions is one order of magnitude less than that of 7Li+. These results clearly indicate that the dominant conduction ion in 15NaI∙LiBH4 is Li+ despite its low concentration (6 mol%). The possibility of Na+ conduction is further investigated by charging a Na/Sn cell using a three-layered electrolyte with 15NaI∙LiBH4 sandwiched by a known Na+ conductor, 75Na2S∙25P2S5. The charging of Sn is interrupted for the three-layered electrolyte, while Sn can be smoothly charged using 75Na2S∙25P2S5 as the single electrolyte. These results confirm that the conduction of Na+ in 15NaI∙LiBH4 is not as significant as that of the guest Li+ ions and strongly suggest that the Li+ ions are the dominant conduction species. The results show the potential of Na compounds as the base materials in novel solid electrolytes for all-solid-state lithium batteries.

In this work, a cationic porphyrin, ascribed as [Ttolyl(P-(C6H5)3)4]4+, where Ttolyl = 5,10,15,20 tetrakistolylporphyrin, was electrostatically assembled with CdTe quantum dots capped with glutathione (GSH) of diameter ~3.28 nm via a layer-by-layer methodology. This multilayer assembly was evaluated as a biocompatible interface with synergic effects for calf thymus double-stranded DNA (CT DNA) immobilization, considering that the hybrid assembly contains a cationic porphyrin with a high binding constant for CT DNA, and quantum dots with polypeptide as a capping agent. The multilayer assembly, ascribed as ITO/{[Ttolyl(P-(C6H5)3)4]4+/CdTe} n (n = 1–5), was characterized by UV-Vis spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The last technique was explored in order to check the adsorption of CT DNA onto the multilayer porphyrin/quantum dot assembly. The difference in electron transfer resistance (ΔR ct) obtained after CT DNA incubations showed the best result for a specific multilayer assembly, n = 3. {[Ttolyl(P-(C6H5)3)4]4+/CdTe}3 showed a good correlation of ΔR ct with the logarithmic concentration of CT DNA, in the range 1.0 × 10−10 to 1.0 × 10−6 M with a limit of detection (LOD) of 1.5 × 10−12 M. Conversely, when the {[Ttolyl(P-(C6H5)3)4]4+/CdTe}3 system was incubated with calf thymus single-stranded DNA and salmon testes DNA, no significant difference in ΔR ct was observed. We conclude that the newly described {[Ttolyl(P-(C6H5)3)4]4+/CdTe} n system is a choice method for the impedimetric determination of CT DNA.

Composite polymer electrolyte films comprising polyethylene oxide (PEO) as the polymer host, LiClO4 as the dopant, and NiO nanoparticle as the inorganic filler was prepared by solution casting technique. NiO inorganic filler was synthesized via sol-gel method. The effect of NiO filler on the ionic conductivity, structure, and morphology of PEO-LiClO4-based composite polymer electrolyte was investigated by AC impedance spectroscopy, X-ray diffraction, and scanning electron microscopy, respectively. It was observed that the conductivity of the electrolyte increases with NiO concentration. The highest room temperature conductivity of the electrolyte was 7.4 × 10−4 S cm−1 at 10 wt.% NiO. The observation on structure shows the highest conductivity appears in amorphous phase. This result has been supported by surface morphology analysis showing that the NiO filler are well distributed in the samples. As a conclusion, the addition of NiO nanofiller improves the conductivity of PEO-LiClO4 composite polymer electrolyte.

Electroless and electroplated nickel electrodes are extensively used for hydrogen evolution reaction (HER). In the present work, TiO2-supported IrO2 mixed oxide composite was prepared and used to reinforce Ni–P electroless plates to be used as catalytic electrodes for HER. The electrodes exhibited high electrocatalytic activity when the electrodes were used for HER. All the parameters including particle size of the catalyst, surface roughness, and surface active sites were studied. The particle size of the IrO2 catalyst in the mixed oxide was found to have high influence on the catalytic activity of the electrodes. Low overpotential as low as 70 mV at a current density of 200 mA cm−2 was achieved with the mixed oxide-reinforced Ni–P electrodes.

Thick films of pure polyvinyl alcohol and polyvinyl alcohol doped with silver nitrate with different compositions have been prepared by solution cast technique. The FT-IR spectrum confirms the complexation process. The conductivity of the pure polyvinyl alcohol is of the order of 10−7 Sm−1 at 90 °C, and its value increases by two orders of magnitude when doped with 20 wt% of AgNO3. The activation energy, calculated from the Arrhenius plot for all compositions of the poly vinyl alcohol doped with silver nitrate, is between 0.24 and 0.35 eV. The migration energy for the ion in polymer electrolyte has been calculated from the modulus spectrum, and is in good agreement with the activation energy calculated from the Arrhenius plot. The modulus spectra indicate the non-Debye nature of the material.