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Surface modification of Fe2O3 by adding BeO was synthesized and calcined at different temperatures of 200-600 °C. The adsorbents were characterized by using XRD, N2 adsorption-desorption isotherm prior to performing CO2 adsorption and desorption studies. The CO2 adsorption data were analyzed using adsorption isotherm models such as Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich. BeO/Fe2O3-300 that calcined at 300 °C showed the most efficient adsorbent with physisorption and chemisorption were measured at 5.85 and 45.88 mg/g respectively. The CO2 adsorption notably best fitted with Freundlich isotherm with R2 = 0.9897 and calculated adsorption capacity closest to experimental data. This implies the CO2 adsorption process was governed by multilayer adsorption on the heterogeneous surface of the adsorbent. The mean free energy of adsorption (E=3.536 kJ/mol) from Dubinin-Radushkevich and heat of adsorption (bT=3.219 kJ/mol) from the Temkin model support that the adsorption process is physical phenomena.

[C40H28F3IrN5O]PF6, monoclinic, P21/c (no. 14), a = 20.2282(19) Å, b = 14.5095(11) Å, c = 12.6091(10) Å, β = 96.937(3)°, V = 3673.7(5) Å3, Z = 4, Rgt(F) = 0.0498, wRref(F2) = 0.1250, T = 107(2) K.

Nano-composite polymer electrolyte (NCPE), poly(vinylidenefluoride-hexafluoropropylene)-poly(methylmethacrylate) grafted natural rubber with lithium tetrafluoroborate and zirconia (PVdF-HFP/MG49-LiBF4-ZrO2) was prepared by a facile one-pot in situ sol–gel method. The influence of zirconia nano-fillers on the electrochemical, chemical and structural properties of polymer electrolyte was investigated. The interaction of polymer electrolyte and zirconia was explored via density functional theory (DFT). Electrochemical impedance spectroscopy study showed that the optimum ionic conductivity is 2.39 × 10−3 S cm−1 (6 wt% zirconia). X-ray diffractogram results revealed a decreasing trend of crystalline phases and no lithium salt peaks were observed upon the addition of zirconia. As a result, the LiBF4 salt was well-solvated in the polymer matrix with a one-fold increase in lithium transference number. Remarkably, a good electrochemical stability was achieved at 6.9 V from a linear sweep voltammetry (LSV) analysis. Observations from the infrared spectra indicate that chemical interactions occurred at the carbonyl and fluoride functional groups and is further corroborated by DFT studies. Micrograph images showed that the zirconia nano-particles were successfully produced (7–15 nm). The nanocomposite polymer electrolyte possesses promising charge/discharge performance and has the potential to be applied in lithium-ion polymer battery.

Mononuclearmolybdenum complex with the general formula [MoTp*(NO)I(X)], where Tp* =tris(3,5-dimethylpyrazolyl)hidroborate and X =1,4-bis(pyridin-4-ylethynyl)benzene) was found to exhibit the required chemical and physical properties as a photosensitiser in photoelectrochemical cell. The complex was structurally characterised by infrared, UV-Vis and electrochemical analysis. TiO2 electrode films were prepared by paste technique and characterised by SEM and XRD. Photoelectrochemical properties of [MoTp*(NO)I(X)]-sensitisedTiO2 photoelectrode were carried out in 1.0 M NaOH electrolyte with a SCE reference electrode and a platinum counter electrode. The [MoTp*(NO)I(X)]-sensitised TiO2 photoelectrode showed positive photoinduced current compared to unsensitised TiO2 photoelectrode.

Ru(II) bipyridyl photocatalyst with the formula, [Ru(bpy)2(o-CH3-bzpypz)](PF6)2] (Ru01) and [Ru(bpy)2(o-Cl-bzpypz)](PF6)2] (Ru02), where bpy = 2,2’-bipyridyl, o-CH3-bzpypz = (3-(pyridin-2-yl)-1H-pyrazol-1-yl)(o-tolyl)methanone and o-Cl-bzpypz = (2-chlorophenyl)(3-(pyridin-2-yl)-1H-pyrazol-1-yl)methanone, has been successfully synthesized and characterized on the basis of C, H, N elemental analysis, IR, UV-Vis and NMR spectroscopy. Both Ru(II) complexes showed Infrared stretching frequencies at 1742-1736 cm−1 v(C=O), 1605 cm−1 v(C=N) and 842-837 cm−1 v(PF). Full geometry optimization of the complex structures were carried out using DFT method with B3LYP exchange-correlation functional and 6-31G (d,p) basis-set for H, C, N, O and Cl; and LAN2LDZ basis set as effective core potential for the ruthenium centre. The highest-occupied molecular orbital (HOMO) energy levels of Ru01 and Ru02 are −5.63 and −5.55 eV, respectively. The photocatalytic properties of the Ru(II) complexes were evaluated by studying the de...

A photocatalytic degradation of bromothymol blue (BTB) by a ruthenium(II) complex at basic buffer of 12 has been investigated. A novel ruthenium(II) complex, [Ru (bpy)2(Phen-pBrBT)](PF6)2, where bpy = 2,2'-bipyridine, (Phen-pBrBT) = N-(p-bromobenzoyl)-N'-(1,10-phenanthrolin-5-yl)thiourea was synthesized and characterized by spectroscopic techniques namely infrared, ultraviolet-visible (UV-Vis) and nuclear magnetic resonance. The photocatalytic performance of the ruthenium(II) complex was studied in two different concentrations of bromothymol blue (2.5 × 10-5 and 10.0 × 10-5 M). Upon exposure to light source, the optical absorption of bromothymol blue decreased gradually with time in the presence of [Ru(bpy)2(Phen-pBrBT)](PF6)2. The second order kinetic model of bromothymol blue photodegradation at pH=12.00 was established. The rate of photodegradation was found to be directly proportional to the concentration of bromothymol blue in aqueous solution.