Biodegradable solid polymer electrolyte (SPE) is prepared by solution-casting technique using low-cost cellulose derivative, hydroxypropylmethyl cellulose (HPMC) as a host polymer. Owing to the hydrophobic nature of this polymer, it is predicted to exhibit low ionic conductivity upon addition of magnesium trifluoro methanesulfonate (MgTf 2 ) salt. Therefore, ionic liquid (IL), 1-butyl-3-methylimidazolium trifluoro methanesulfonate (BMIMTf), is added in order to enhance its ionic conductivity. Based on the findings, the ionic conductivity at room temperature and the dielectric behaviors of the SPE complex improved upon incorporation of 40 wt.% IL. On top of that, addition of IL reduces the degree of crystallinity and the glass transition temperature (T g ) of the SPE. The conductivity-temperature plot revealed that the transportation of ions in these films obey Arrhenius theory. The interaction between SPE complex, MgTf 2 salt, and BMIMTf is investigated by means of Fourier transform infrared (FTIR) spectroscopy through the change in peak intensity around 3413, 1570, and 1060 cm −1 , which are responsible for -OH stretching band, C-C and C-N bending modes of cyclic BMIM + , and C-O-C stretching band, respectively.

A series of density functional theory calculations were performed to understand the bonding and interaction of hydrogen adsorption on two-dimensional silicon carbide obtained from molecular dynamics simulation. The converged energy results pointed out that the H atom can sufficiently bond to 2D SiC at the top sites (atop Si and C), of which the most stable adsorption site is TSi. The vibrational properties along with the zero-point energy were incorporated into the energy calculations to further understand the phonon effect of the adsorbed H. Most of the 2D SiC structure deformations caused by the H atoms were found at the adsorbent atom along the vertical axis. For the first time, five SiC defect formations, including the quadrilateral-octagon linear defect (8-4), the silicon interstitial defect, the divacancy (4-10-4) defect, the divacancy (8-4-4-8) defect, and the divacancy (4-8-8-4) defect, were investigated and compared with previous 2D defect studies. The linear defect (8-4) has the lowest formation energy and is most likely to be formed for SiC materials. Furthermore, hydrogen atoms adsorb more readily on the defect surface than on the pristine SiC surface.

We prepared single-phase Nax(H3O)zCoO2·y'H2O with varying amount of Br2 volume in acetonitrile, and examined the Na + content (x), H3O + content (z), H2O content (y') and Tc. By changing the amount of Br2 during preparation, the amount of x in Nax(H3O)zCoO2·y'H2O was controlled from 0.282 to 0.359. It was found that superconductivity is not correlated with Co valence but with y'/x, that is, the coordination number of Na + with H2O, and secondly with x/x+z, that is, the ratio of Na + ion in the (Na + + H3O + ) site, suggesting that shielding effect of Nax(H3O)zCoO2·y'H2O governs superconductivity.

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The effects of elemental substitutions at the Tl site of a Tl1−xXx(Ba, Sr)CaCu2O7 superconductor with X = Cr, Bi, Pb, Se, and Te were investigated. This study aimed to determine the elements that enhance and suppress the superconducting transition temperature of the Tl1−xXx(Ba, Sr)CaCu2O7 (Tl-1212) phase. The selected elements belong to the groups of transition metal, post-transition metal, non-metal, and metalloid. The relationship between the transition temperature and ionic radius of the elements was also discussed. The samples were prepared by the solid-state reaction method. The XRD patterns showed a single Tl-1212 phase was formed in the non- and Cr-substituted (x = 0.15) samples. The Cr-substituted samples (x = 0.4) showed a plate-like structure with smaller voids. The highest superconducting transition temperatures (Tc onset, Tcχ′, and Tp) were also achieved by the Cr-substituted samples for x = 0.4 compositions. However, the substitution of Te suppressed the superconductivity of the Tl-1212 phase. Jc inter (Tp) for all samples was calculated to be in the range of 12–17 A/cm2. This work shows that substitution elements with a smaller ionic radius tend to be more favorable in improving the superconducting properties of the Tl-1212 phase.