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In this paper, we presented structural, Fourier infrared spectroscopic, and dielectric analysis of cobalt chromate (Co2+Cr23+O4) with various percent gadolinium (Gd3+) rare-earth metal additions under humidity and non-humidity circumstances. The major goal of this research is to develop more robust and sensitive humidity sensor materials. The Gd3+-doped Co2+Cr23+O4 samples are produced using a modified solution combustion process and sintered for 2 h at 650 °C to demonstrate the influence of Gd3+ on structural, Fourier Infrared spectroscopic, dielectric with constant frequency and presence of humidity characteristics. X-ray powder diffraction (XRD) analysis provides the detailed formation of the Co2+Cr23+O4 phase. Furthermore, the average crystallite sizes are 7 to 9 nm for Gd3+-doped Co2+Cr23+O4. The general nature of ferrite materials is revealed via FTIR analysis. Our research focus on the properties of permittivity and electrical conductivity with Gd3+ addition, constant frequency, and humidity. We studied the relevant conductivity of the samples, the response time of the capacitive sensor, and the humidity influence, at the constant frequency level, on the characteristics of the relative permittivity at a constant frequency range of f = 1 kHz. Our results suggest that the Gd3+ doped Co2+Cr23+O4 can be used as an active material for humidity sensor applications. [ABSTRACT FROM AUTHOR]

It's indeed critical to improve our understanding of how functional materials work in order to design the next generation of materials in their domains. We chose LuFeO3 and Lu(YFe)O3 to study the electronic structural and spectroscopic properties using X-ray photoelectron spectroscopy and Mössbauer spectra to accomplish this. LuFeO3 and Lu0.2Y0.8FeO3 were prepared by the solution combustion method using carbamide and glucose as fuel. As-synthesized samples sintered at 1250 °C to get single phase. X-ray diffraction patterns of LuFeO3 nanoparticles confirm the orthorhombic structure and Lu0.2Y0.8FeO3 nanoparticles confirm the major orthorhombic structure and minor hexagonal structure. Crystallite size decreases after the substitution of Y3+ on LuFeO3. X-ray photoelectron spectra were excited with a monochromatized AlK _-line radiation. Absolute resolved energy interval was 0.6 eV, which was determined with the Ag3d5/2 line. The diameter of the X-ray spot on a sample was 500 mm; it was small enough to study the samples obtained. The sample of the composition Lu0.2Y0.8Fe O3 contains approximately 10 times less LuFeO3. The spectra are split into components that correspond to the valence locations of Y3d, Fe3d, and Lu 4f states in yttrium, iron, and lutetium, respectively. It can be seen that the addition of yttrium does not strongly displace the valence band components related to the densities of Y3d, Fe3d, and Lu 4f states in the Lu0.2Y0.8FeO3 sample as compared to nanoparticles of the LuFeO3 composition. Fe2p3/2,1/2—X-ray photoelectron spectra in both samples have similar energies. In addition, both spectra have charge transfer satellites located at about 718.2 eV between the Fe2p3/2 and Fe2p1/2 peaks. Mössbauer spectra of LuFeO3 and Lu0.2Y0.8FeO3 were collected in the temperature range of 13–700 K. At 700 K, the spectra of both samples are paramagnetic doublets with similar parameters. At the lowest temperature (14 K), the spectra of both samples are magnetically split sextets. The isomer shift values of the sextets and doublets are typical for Fe3+ ions in oxygen octahedron. [ABSTRACT FROM AUTHOR]

The Ag-mixed Se 70 Te 30 thermally deposited semiconducting thin films show interesting thermoelectric properties. As the Ag content in the structure of Se 70 Te 30 increases, the Seebeck coefficient increases. The semiconductive thin films reveal a p-type behavior. The dark conductivity increases at 300 K, whereas a reduction in corresponding activation energy for dark, photo and thermal response is observed with the increase in the Ag content. It is elucidated that the power factor for Se 70 Te 30 100 - x Ag x (0.0 ≤ x ≤ 8.0 at. %) semiconducting thin films can be tuned and enhanced at varied temperature ranges through adjusting the addition amount of Ag. These results indicate that these semiconducting thin films have remarkable potential as thermoelectric generators. [ABSTRACT FROM AUTHOR]