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Dimethylsulfone (DMSO2), a small organic molecule, was observed to induce the alignment of poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT:PSS) via in-situ crystallization in PEDOT:PSS mixture, which was verified by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). A chemically stable dopant, DMSO2, remarkably raised the electrical conductivity of the PEDOT:PSS film, which was fabricated from pre-mixed solution of PEDOT:PSS and DMSO2, up to 1080 S/cm, and more importantly, such a PEDOT:PSS film showed a long-term humidity stability and it retained near 90% electric conductivity after 60 days, suggesting DMSO2 is promising for an eco-friendly alternative to replace dimethyl sulfoxide (DMSO), ethylene glycol (EG) and various acids dopants that have been widely employed to dope and post-treat PEDOT:PSS. Pairwise interaction energies and free energy of solvation between PEDOT:PSS and DMSO2 were calculated by first-principles and molecular mechanics, respectively, revealing the mechanism of DMSO2 in enhancing the electrical conductivity.

Abstract: In the present work, we provide a dielectric study on dimethylsulfone (DMSO2) solutions in water and dimethylsulfoxide (DMSO) in the frequency range from 100MHz to 50GHz and for temperatures from 298.15 to 318.15K. The dielectric data are parametrized utilizing a Cole–Davidson spectral function, which presumes an unsymmetrical relaxation time distribution. The conductivity contribution to the total relaxation must be taken into account only in an aqueous solution of DMSO2. The concentration dependent static dielectric constant (εS), relaxation time (τ) and relaxation strength (Δε) of these solutions have been determined. [Copyright &y& Elsevier]

Abstract: In this paper the densities and enthalpies of solution of dimethylsulfone (DMSO2) in dimethylsulfoxide (DMSO) and DMSO/water equimolar mixture have been measured over available concentration range (up to about 1molkg−1). Densities of solutions and apparent molar volumes were determined over the 293.15–323.15K temperature range. In DMSO2–DMSO–water system the strongest interaction between DMSO and water molecules leads to the increase of partial molar volumes for DMSO2. It was shown that the competitive intermolecular interactions are responsible for the observed phenomena. Solution enthalpies of DMSO2 in the above mentioned solvents and the enthalpies of transfer of DMSO2 from water to DMSO and DMSO/water mixture have been calculated. The obtained results confirm that the endothermal process of sulfone crystalline lattice decomposition predominates during the dissolution of sulfones. With the transfer of DMSO2 from water to DMSO and mixed solvent the endothermic increase of transfer enthalpies takes place. [Copyright &y& Elsevier]

Raman and IR absorption spectra were studied and molecular relaxation characteristics of vibrations of the anion and solvent were calculated for an xLiNO-(1 - x)(CH)SO system ( x = 0.1, 0.2, 0.3, 0.4 M). It was found that it is impossible to increase the concentration of free ions involved in charge transfer in such a system by either increasing the temperature or changing the concentration composition in the studied range of x. [ABSTRACT FROM AUTHOR]

Abstract: The mild catalytic oxidation of dimethylsulfoxide (DMSO) into biodegradable dimethylsulfone is proposed as an efficient pretreatment of wastewaters subjected to biological treatment processes. A SiO2–TiO2 mesoporous xerogel prepared by a non-hydrolytic route, as well as titanium silicalite TS-1 showed very good activity and stability in the catalytic oxidation of DMSO with H2O2 in dilute aqueous solution, at room temperature. [Copyright &y& Elsevier]

An effective method for removing dimethylsulfoxide (DMSO) from wastewater, based on the mild selective catalytic sulfoxidation with H2O2, is proposed in this study. The catalysts are W-containing layered double hydroxides (LDH), and they were obtained by ionic exchange of the nitrate anions from MAl-LDH precursors (M=Mg2+ or Zn2+) with both and species. Results of X-ray diffraction (XRD), N2 adsorption, thermal gravimetric analysis (TGA), diffuse reflectance ultraviolet spectroscopy (DRUV) and Raman spectroscopy confirmed the formation of the W-oxospecies inside the interlayer space and the modification of the textural properties upon the exchange process. All catalysts showed very good activity and stability in the DMSO conversion into dimethylsulfone with dilute H2O2 aqueous solution, at low temperatures (20–50°C). The efficiency of the H2O2 was higher than 95% and the behaviour of the water as solvent was very close to that of the organic solvents (ethanol, acetonitrile, 1,4-dioxane). [Copyright &y& Elsevier]

Volatile organic sulfur compounds (VOSCs) play a major role in the global sulfur cycle. Two components, dimethyl sulfide (DMS) and methanethiol (MT) are formed in large amounts by living systems (e.g. algae, bacteria, plants), particularly in marine environments. A major route to DMS is by action of a lyase enzyme on dimethylsulfoniopropionate (DMSP). DMSP has other roles, for instance as an osmoprotectant and cryoprotectant. Demethiolation of DMSP and other materials leads to MT. A major transport process is release of DMS from the oceans to the atmosphere. Oxidation of DMS in the atmosphere by hydroxyl and nitrate radicals produces many degradation products including CO2, COS, dimethyl sulfoxide, dimethyl sulfone, organic oxyacids of sulfur, and sulfate. These materials also have roles in biotic processes and there are complex metabolic interrelationships between some of them. This review emphasizes the chemical reactions of the organic sulfur cycle. For biotic reactions, details of relevant enzymes are provided when possible. [Copyright &y& Elsevier]