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The innovative investigation into Mn:Co3O4 samples through a multifaceted approach encompassing diverse characterization methodologies and electrochemical assessments. Employing X-ray diffraction, we unveiled the internal geometry and crystallite disposition, which impeccably matched the spinel-cubic structure of Co3O4. X-ray photoelectron spectroscopy analysis meticulously corroborated the existence of Co, Mn, and O elements while unveiling distinctive valence states for Co and Mn ions. On further analysis, scanning electron microscopy provides a visual insight into granular, hexagonal-shaped layered structures, with varying pore abundance among the all temperatures. The compositional integrity is confirmed through energy-dispersive X-ray spectroscopy. Electrochemical investigations encompass cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The CV curves exhibit redox peaks denoting pseudo-capacitive behavior, while GCD profiles display symmetric behavior. The specific capacitance at various scan rates highlights the superior performance of the Mn:Co3O4 sample at 700 °C. EIS analyses affirm low interfacial charge resistance and accelerated ion diffusion. Cyclic stability assessment over 1500 cycles underscores the enduring process of Mn:Co3O4 culminating in a favorable specific capacitance of 625 F/g and a remarkable capacity retention of 96% even after 1500 cycles. [ABSTRACT FROM AUTHOR]

The harvesting of renewable energy storage has prompted extensive study on the energy storage devices, chiefly batteries and supercapacitors. Electrodes made up of nano-architecture arrays are promising candidate to strengthen the electrochemical performance of the energy storage devices. In this work, nano-sized Co3O4 materials have been prepared by facile coprecipitate technique. The materials were characterized by XRD, FTIR, SEM, EDAX, HR-TEM and XPS. The TEM studies confirmed the existence of nano-rods of length ranges from 50 to 160 nm. The electrochemical studies were carried out using three-electrode system. The Co3O4 electrode material exhibited prominent specific capacitance of 373.84 F g−1 at the current density of 1.5 A g−1 with superior cyclic stability of 92% after 1000 cycles. The Co3O4 nanorods are attributed to high surface to volume ratio which results in more provisions for active sites and in turn enhance the redox reactions. Also the EIS studies reveal the diffusive charge transfer mechanism that enhances the accumulation of charges. The results imply that Co3O4 nanoparticles would be a promising material for electrodes in supercapacitors. [ABSTRACT FROM AUTHOR]

In this paper, we synthesized LaPO4 and In doped LaPO4 nanoparticles (NPs) with different concentrations (In-5%, 7.5%, and 10%) by the Co-precipitation method with calcined at 800 °C. The monoclinic phase with enhanced crystalline size was shown by the annealing temperature at 800 °C, which occurred in the XRD pattern. IR spectroscopy proved the presence of the phosphate group in the region of 1200 to 400 cm−1. FE-SEM images of the pure and doped higher concentrated NPs showed spherical agglomerates and dense aggregate layer structure. X-ray photoelectron spectroscopy (XPS) analysis reveals that In3+ and La3+ have a prominent appearance in the XPS study, which supports the synthesis of In-LaPO4 nanoparticles and contradicts the findings of XRD and FTIR. The optical characteristics are evaluated by UV DRS from estimated using the Kubelka Munk function, bandgap values are reduced while increasing the dopant concentration. Moreover, the fabricated metal–insulator-semiconductor (MIS) Schottky barrier diode uses In-LaPO4 NPs as an interfacial layer. The thermionic emission (TE) model determines ideality factor (n), barrier height (ϕB), and reverse saturation current (IO) are all determined from the I–V characteristics. Under light irradiation, the lowest ideality factor of 2.88, and the barrier height of 0.744 eV were achieved. [ABSTRACT FROM AUTHOR]

Pure and cerium (Ce) doped tin oxide (SnO) thin films are prepared on glass substrates by jet nebulizer spray pyrolysis technique at 450 °C. The synthesized films are characterized by X-ray diffraction (XRD), scanning electron microscopy, energy dispersive analysis X-ray, ultra violet visible spectrometer (UV-Vis) and stylus profilometer. Crystalline structure, crystallite size, lattice parameters, texture coefficient and stacking fault of the SnO thin films have been determined using X-ray diffractometer. The XRD results indicate that the films are grown with (110) plane preferred orientation. The surface morphology, elemental analysis and film thickness of the SnO films are analyzed and discussed. Optical band gap energy are calculated with transmittance data obtained from UV-Visible spectra. Optical characterization reveals that the band gap energy is found decreased from 3.49 to 2.68 eV. Pure and Ce doped SnO thin film gas sensors are fabricated and their gas sensing properties are tested for various gases maintained at different temperature between 150 and 250 °C. The 10 wt% Ce doped SnO sensor shows good selectivity towards ethanol (at operating temperature 250 °C). The influence of Ce concentration and operating temperature on the sensor performance is discussed. The better sensing ability for ethanol is observed compared with methanol, acetone, ammonia, and 2-methoxy ethanol gases. [ABSTRACT FROM AUTHOR]