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Herein, a new energy cycle called the "hydrogen iodide (HI) cycle" is proposed that involves the repeated generation of solar hydrogen and battery power. Solar hydrogen generation using an HI solution allows for the use of a narrow‐bandgap photocatalyst. It is demonstrated that the addition of single‐walled carbon nanotubes (SWCNTs) effectively enhances solar hydrogen generation from HI solution with methylammonium lead iodide. Electron microscopy observations and spectroscopic experiments reveal that SWCNTs improve hydrogen generation by adsorbing byproduct iodine molecules. Additionally, a zinc‐iodine battery, utilizing paper I@SWCNTs recovered from the photocatalyst test cell and zinc metal, operates efficiently with an initial cell voltage of approximately 1.2 V. The battery's capacity, corresponding to the amount of encapsulated iodine molecules, indicates that SWCNTs can effectively adsorb the byproduct iodine molecules within the photocatalyst test cell. It is also discussed that the electrolyte solution after the discharge experiment should include iodide ions, indicating that the solution after battery discharge returns to the starting point of the "HI cycle." Raman measurements reveal that I@SWCNTs are transformed back into empty tubes during the discharge experiment. Therefore, SWCNTs can be repeatedly used in the new cyclic energy scheme referred to as the "HI cycle." [ABSTRACT FROM AUTHOR]

Reduction of styrene compounds was achieved by the simple method of adding more than 2.5 equivalents of an aqueous HI solution in chlorobenzene under refluxing conditions for 8 h to give the product in medium to excellent yields. There was no need to add further additional reagent and catalyst. HI was a specific reagent for this reduction reaction. Increment of the amount of HI was efficient to increase the yield rather than to elongate the reaction time. This reaction could be applied to compounds bearing halogen and sulfur atoms, which would act as reductive site and poisoning of the transition-metal catalyst, respectively. The yield was decreased in the case of the compounds bearing small substituent such as propyl and butyl groups on olefin. This reaction proceeded via the iodinated intermediate followed by the reduction of C-I bond. The reduction mechanism would contain the radical cleavage of the C-I bond. [ABSTRACT FROM AUTHOR]

The effect of HI and O2 plasma treatments on a Ge surface is studied by X-ray photoelectron spectroscopy. Ge oxide on a Ge surface can be effectively removed at room temperature by remote HI plasma in inductively coupled plasma reactive ion etching system without substrate bias. The re-oxidation of oxide-free HI plasma-treated Ge has been performed sequentially by O2 plasma. By utilizing HI and O2 plasma treatment cyclically, we have proved the viability of Ge digital dry etching. Ge digital dry etching by controlling the plasma power and the processing time of HI and O2 plasma treatments will be the building block for achieving Ge atomic layer etching. [ABSTRACT FROM AUTHOR]

The experimental results for the concerted molecular decomposition of alkyl iodides RI to olefin and HI were analyzed in terms of the intersecting parabolas model (IPM). The activation energies ( E) and rate constants ( k) of the earlier unstudied reactions of the concerted molecular decomposition of RI were calculated on the basis of the enthalpy of the reaction and IPM algorithms. The factors that influence on E of RI decay were established: the enthalpy of the reaction, the energy of stabilization of radical R*, the length and force constant of the C-I bond, and the size of the halogen atom. The values of E and k for the backward reactions of HI addition to olefins were estimated. [ABSTRACT FROM AUTHOR]

I crystallization could be a technical option in HI decomposition section of SI thermochemical water splitting process to increase process efficiency. Design of a crystallizer requires experimental data as well as corresponding equations for thermophysical properties of HI solution, which is a named ternary solution of HO, HI, and I. However, so far, there are no available analyses on them. We collected experimental data and corresponding equations with temperature parameters and compared the equations with the data to analyze their accuracy and credibility. Thermal conductivity was updated in this work while keeping a structure of a corresponding equation. Relative deviations were estimated for liquid density, thermal conductivity, viscosity, and heat capacity and summarized with temperature for HO, HI, and I. Solution density and viscosity of binary HO-HI solution were also analyzed with an empirical equation under a limited condition and with predictable methods exhibiting satisfactory consistency. [ABSTRACT FROM AUTHOR]

It is shown that both graphite oxide (GO) and oxidized graphene nanoribbons (OGN) can be safely reduced by using hydrogen iodide (hydroiodic acid). FT-IR spectroscopy and TGA-DTG were used to show that HI 67% is able to lead to a complete reduction of GO while HI 57% is less effective. In terms of FT-IR spectroscopy and thermal analysis, the HI-reduced GO is almost identical to the N2H4-reduced GO. Hydrogen iodide 57% is in any case effective in reducing OGN. Since hydrazine is extremely toxic and explosive when anhydrous, it is suggested to use HI (preferably at 67% concentration) as alternative, safe and effective reducing agent. [ABSTRACT FROM AUTHOR]

C60 fullerene can be easily hydrogenated in aromatic solvent under mild conditions with aqueous hydrogen iodide (HI). The resulting black product has the molecular formula C60H24•2I2 on the basis of the FT-IR spectroscopy and of the thermogravimetric analysis. When this compound is heated under N2 it releases I2 and HI producing exclusively C60H18, which was recognized with FT-IR spectroscopy. [ABSTRACT FROM AUTHOR]

The article presents a case study of 48-yr-old non-atopic, never-smoking female chemistry teacher who developed sudden respiratory symptoms. The various tests showed bronchial obstruction and bronchial hyperresponsiveness. She suffered with the Reactive Airway Dysfunction Syndrome (RADS) due to induction by fumes of mixed iodine compounds and even if providing with the proper medication the patient continued to suffer from cough and dyspnoea.

The electric dipole moment and the static dipole polarizability of the hydrogen iodide molecule were studied using sophisticated correlated and relativistic methods. Both scalar and spin–orbit relativistic effects were carefully accounted for. We conclude that the large differences between the theoretical and experimental dipole moment, the dipole moment derivative and the polarizability cannot be reconciled by improved account of electron correlation and relativistic effects. The most striking difference between theory and experiment is observed for the polarizability anisotropy. We believe that experimental data, namely the experimental dipole moment (the most recent value is 0.176 au as compared to our best theoretical estimate, 0.154±0.003 au), the parallel polarizability (44.4 and 38.47±0.05 au) and the anisotropy (11.4 and 2.33±0.05 au) must be inaccurate. Experimental and theoretical perpendicular polarizability components (33.0 and 36.14±0.05 au,) and the mean polarizability (36.8 and 36.92±0.05 au) agree better. Our vibrationally corrected relativistic CCSD(T) results represent the most sophisticated predictions of electric properties of HI obtained so far. [ABSTRACT FROM AUTHOR]