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Ba(Nb x Sn 1- x )O 3 (BNSO) films were epitaxially grown on (001) oriented MgO substrates with Nb doping content from 0.00 to 0.15 by pulsed laser deposition. The structural, electrical, and optical properties of the films were investigated in detail by x-ray diffraction, x-ray photoelectron spectroscopy, Hall effect and transmittance spectroscopy. The lowest room temperature resistivity value of 4.81 × 10 −4 Ω cm with carrier concentration and mobility of 6.59 × 10 20 /cm 3 and 19.65 cm 2 /V was observed in the film at x = 0.05, indicating an excellent electrical conductivity. All the BNSO films exhibit a high transmittance of more than 80% in the visible range. The variation of band gap E g with Nb doping content was interpreted by the Burstein-Moss effect and the occurrence of octahedral tilt distorting. Excellent optical and electrical properties suggest that BNSO films have potential applications in the optoelectronic devices as transparent and conducting oxide material. [ABSTRACT FROM AUTHOR]

• CFO and CCFO electrodes were synthesized by pulsed laser deposition (PLD). • The composition of products can be easily tuned. • The OER activity highly depends on the Cr doping. • The overpotential of CCFO electrode is 293 mV with a Tafel slope 76 mV/dec. • CCFO electrode shows excellent durability and stability. Traditional powder OER catalysts have many disadvantages such as the extremely complicated electrode preparation process. Herein, squama-like Co 0.95 Cr 0.05 Fe 2 O 4 thin film electrode is directly deposited on flexible Ni foam substrate by a novel method of pulsed laser deposition. Cr doping leads to the electrode highly effective for OER, and the current density is about 2.1 times of that compared with undoped CoFe 2 O 4 thin film at 1.8 V. The Co 0.95 Cr 0.05 Fe 2 O 4 thin film exhibits an overpotential of 293.3 mV at 10 mA/cm2 as well as extraordinary stability, which is far better than that of CoFe 2 O 4 thin film and no-load Ni foam. [ABSTRACT FROM AUTHOR]

Transparent and conductive Ta doped BaSnO 3 (BaSn 1−x Ta x O 3 , BSTO) films with x = 0–0.15 were epitaxially grown on MgO single crystalline substrates by a pulsed laser deposition method. The effects of Ta ions incorporation on the microstructure, electrical and optical properties of BSTO films were investigated. X-ray diffraction measurements indicate that the out-of-plane lattice parameters increase gradually with Ta concentration increasing, and the films are relaxed due to the large lattice mismatch between the films and substrate. Atomic force microscopy images reveal that all the films have smooth surface and low roughness. X-ray photoelectron spectra of BSTO films confirm that the Ta ions are presented in the +5 state. The lowest room-temperature resistivity and the highest carrier concentration and Hall mobility were observed in BSTO film at x = 0.07, with the values of 2.525 mΩcm, 5.024 × 10 20 cm −3 , and 4.921 cm 2 /Vs, respectively. Temperature dependent resistivity behavior shows that the BSTO films with low doping content exhibit metal-semiconductor transition at low temperature. The optical transmittances of all BSTO films are more than 80% in the visible region. The optical band gaps were found to increase from 3.52 to 4.23 eV with the increase of Ta doping content and can be attributed to the Burstein-Moss effect. Thus, the superior electrical and optical properties of Ta doped BaSnO 3 films are comparable to that of La and Sb doped BaSnO 3 films, and have potential applications in the optoelectronic devices. [ABSTRACT FROM AUTHOR]

(Ba 1-x Gd x )SnO 3 (BGSO) (x = 0–0.15) films were epitaxially grown on MgO substrates by pulsed laser deposition. Structure analysis was performed using X-ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy. Transport properties were investigated by Hall effect and temperature dependent resistivity measurement. Results show that the film resistivity decreases systematically with increasing Gd doping concentration. The lowest room-temperature resistivity of 6.18 mΩcm was observed in film at x = 0.07, with the metal-insulator transition at 30 K, which was attributed to the formation of a degenerate band in films. Optical transmission spectra measurement shows that all the BGSO films have high transmittance of more than 80% in the visible range. The band gap variation with the Gd doping concentration was interpreted by the Burstein-Moss effect. Excellent optical and electrical properties suggest that BGSO films have potential applications in the optoelectronic devices as transparent and conducting oxide material. [ABSTRACT FROM AUTHOR]

Abstract: The high-quality La0.7Ba0.3MnO3 (LBMO) epitaxial films were deposited on (001) oriented LaAlO3 (LAO) substrates by magnetron sputtering technique. The low temperature electrical transport behavior of the films was investigated in details. In the low temperature ferromagnetic metallic state, a common feature, i.e., the minimum of electrical resistivity, was found in both of the films post annealed in oxygen and argon atmosphere. By taking the unusual combination of factors including spin dependent Kondo-like scattering, electron–electron and electron–phonon interactions into account, the resistivity minimum can be fitted well. It was found that the spin dependent Kondo-like scattering plays an important role in both the films, indicating the intrinsic spin disorder in strongly correlated manganites. Furthermore, in a lower temperature interval 4–25K, a stronger electron–electron interaction was observed in the Ar annealed films, which can be attributed to the enhanced disorder arising from oxygen vacancy. [Copyright &y& Elsevier]