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In recent work, the boron hydride anti-B18H22 was announced in the literature as a new laser dye, and, along with several of its derivatives, its solutions are capable of delivering blue luminescence with quantum yields of unity. However, as a dopant in solid polymer films, its luminescent efficiencies reduce dramatically. Clarification of underlying detrimental effects is crucial for any application and, thus, this contribution makes the initial steps in the use of these inorganic compounds in electrooptical devices based on organic polymer thin films. The photoluminescence behavior of the highly luminescent boron hydrides, anti-B18H22 and 3,3′,4,4′-Et4-anti-B18H18, were therefore investigated. The quantum yields of luminescence and photostabilities of both compounds were studied in different solvents and as polymer-solvent blends. The photophysical properties of both boranes are evaluated and discussed in terms of their solvent-solute interactions using photoluminescence (PL) and NMR spectroscopies. The UV degradability of prepared thin films was studied by fluorimetric measurement. The effect of the surrounding atmosphere, dopant concentration and the molecular structure were assessed.

Nickel nanoparticle–decorated reduced graphene oxide nanocomposites (NiG) were prepared by a one-step microwave-assisted solvothermal method. The as-prepared NiG nanocomposite systems were further heated up to 800 °C under an inert atmosphere (named NiG-800) to modify their structural and electromagnetic properties. Thereafter, these developed NiG-800 nanocomposite systems of rGO and nickel nanoparticles (25 wt.%) were applied as nanofillers (50 wt.% and 70 wt.%) in a SEBS (Polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene) polymer matrix to create NiG-800(50)-SEBS and NiG-800(70)-SEBS nanocomposites. The addition of NiG-800 to SEBS led to an increase of Young’s modulus from 16 (SEBS) to 35 MPa (NiG-800(70)-SEBS) while the maximum elongation is still around 300%. The developed NiG-800(70)-SEBS nanocomposite exhibited high-performance electromagnetic wave absorption (minimum reflection loss RLmin ≈ –48.2 dB at 9.29 GHz) at a low thickness of 2.3 mm in the frequency range of 8.2−12.4 GHz. The prepared NiG-800(70)-SEBS nanocomposite has the potential of an electromagnetic wave absorber. The NiG-800(70)-SEBS nanocomposite reported here has total shielding efficiency > 10 dB at a thickness of 1 mm in the whole frequency range (X-band) with reflection ≈ 50% and absorption ≈ 40% which has the potential for electromagnetic wave absorber applications.

The paper is focused on the investigation of thin polystyrene (PS) films and PS films with incorporated anti-octadecaborane( 22) (anti-B18H22) clusters (PS+B18H22) with a thickness of 450 nm and 290 nm, respectively. The main aim is to describe the vibrational behavior of thin films in dependence on temperature and determine the changes connected with the glass transition of PS. Infrared reflection-absorption spectra were measured and from the plot of spectral region area (Arange) vs. temperature, glass transition temperature (Tg) of PS was extracted. The abrupt change in the course of A of Car-H stretching vs. temperature was assigned to the glass transition. Tg of PS and PS+B18H22 thin film was determined to be 74 °C and 77 °C, respectively. On the other hand, only a continuous decrease of A of C-H stretching vs. temperature was found for both samples indicating that each vibrational motion reacts uniquely on temperature increase. It was further found that anti-B18H22 is not fixed firmly in the thin layer at higher temperatures, because no B-H spectral response was detected above 91 °C. This result was also supported with TGA and DSC analysis showing a particular mass decrease at temperature 75 °C.