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In this paper, we report the synthesis of boron doped C3N4/NiFe2O4 nanocomposite and its application as a visible-light photocatalyst for the degradation of methylene blue (MB). Boron-doped C3N4 (BCN) was prepared by simple thermal condensation of dicyandiamide with boric acid, and NiFe2O4 nanoparticles were prepared by the simple sol-gel method. The as-synthesized nanocomposite materials were characterized and confirmed by the X-ray diffraction spectroscopy, Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, UV–Visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The photocatalytic activity of BCN/NiFe2O4 nanocomposite was evaluated towards the degradation of MB in the presence of visible light irradiation. The obtained results confirmed that BCN/NiFe2O4 composite has higher degradation efficiency (98%) than that of BCN and NiFe2O4. Keywords: Thermal condensation, Sol-gel method, BCN/NiFe2O4 nanocomposite, Visible-light photocatalyst, Methylene blue

Sonochemical synthesis was employed to make the intrinsic defects in TiO2 (P25) which facilitates good photocatalytic properties. Thereby, the P25 samples are sonicated for various sonication time intervals with the constant pH and temperature. The ultrasonically modified TiO2 nanoparticles were analyzed by various characterization techniques to obtain the information on the crystallinity, band gap, surface morphology, and electron-hole recombination phenomena. These modified TiO2 samples were applied to the photocatalytic oxidation of ethanol and studied their oxidation mechanism by using in-situ FTIR (DRIFT) technique under UV–visible light irradiation. The DRIFT results revealed that the extension of the ultrasonication time yields good photocatalytic performance due to the oxygen deficiencies. Comparatively, the ultrasonically modified TiO2 exhibited the high conversion rate for the ethanol oxidation than the pristine. Keywords: Photocatalyst, DRIFT, Oxygen deficiency, Ethanol oxidation, Ultrasound irradiation

In this study, four different kinds of perovskite powders (LaMnO3, LaFeO3, LaCrO3, and LaNiO3) were prepared and investigated as anode materials for supercapacitor. The as-prepared powders were blended with active carbon and subsequently coated on the nickel plates as the collector layer of the supercapacitors. Three different types of the aqueous solutions (3 M KCl, 1 M LiOH, and 3 M LiOH) were respectively served as the electrolytes for the supercapacitor. The morphology and crystalline phase were characterized by transmission electron microscopy and XRD. The electrical capacity and impedance were measured by the electrochemical capacitance voltage analyzer and impedance spectroscopy. The profiles of specific capacitance of the four different anodic electrodes and three different electrolytes were implemented. The impedance results indicated that four asymmetric pseudocapacitors didn’t show any Warburg-type line and semi-circle line in the low-frequency region. According to the CV profiles, the intrinsic LaNiO3 exhibits the highest specific capacitance of 106.58 F/g in 3 M LiOH. Furthermore, the 98% of the initial capacitance of LaNiO3 was retained after 500 charge-discharge life cycles at the maximum current density of 1 A/g. The efficient charge storage of LaNiO3 was attributed by the anion intercalated redox reactions along with the suitability of electrode-electrolyte interactions. Keywords: Perovskite, Lanthanum nickel oxide, Pseudocapacitance, Asymmetric supercapacitor, Oxygen de-intercalation