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Usually, modulating electrical transport properties is a vital means to improve the light-induced transverse thermoelectric (LITT) effect. The manganese perovskite-type oxides La1−xAxMnO3 (A = Ca, Sr, etc.) are typical materials with the LITT effect. However, much attention is paid to La1−xCaxMnO3, and few studies focus on low-resistivity La1−xSrxMnO3. In this work, the La1−xSrxMnO3 (0.08 ≤ Sr ≤ 0.7) thin films with inclined structures are prepared based on the metal-organic chemical vapor deposition (MOVCD) method. The XRD and TEM results indicate that La1−xSrxMnO3 (0.08 ≤ Sr ≤ 0.7) thin films feature high c-axis orientation and good biaxial textures. Adjusting Sr content modulates the electrical transport properties of the thin films, the response voltage is significantly improved. Especially, the lowest resistivity of 0.2 × 10−2 Ω·cm is achieved in La0.7Sr0.3MnO3 thin film, thus achieving a fast response time of 24 ns upon the irradiation of a 248 nm pulse laser, significantly lower than most literature results for La1−xCaxMnO3. This work demonstrates the potential of La1−xSrxMnO3 in ultraviolet pulse laser detectors. [ABSTRACT FROM AUTHOR]

The γ-rays are widely and abundantly present in strong nuclear radiation environments, and when they act on the camera equipment used to obtain environmental visual information on nuclear robots, radiation effects will occur, which will degrade the performance of the camera system, reduce the imaging quality, and even cause catastrophic consequences. Color reducibility is an important index for evaluating the imaging quality of color camera, but its degradation mechanism in a nuclear radiation environment is still unclear. In this paper, the γ-ray irradiation experiments of CMOS cameras were carried out to analyse the degradation law of the camera’s color reducibility with cumulative irradiation and reveal the degradation mechanism of the color information of the CMOS camera under γ-ray irradiation. The results show that the spectral response of CMOS image sensor (CIS) and the spectral transmittance of lens after irradiation affect the values of a* and b* in the LAB color model. While the full well capacity (FWC) of CIS and transmittance of lens affect the value of L* in the LAB color model, thus increase color difference and reduce brightness, the combined effect of color difference and brightness degradation will reduce the color reducibility of CMOS cameras. Therefore, the degradation of the color information of the CMOS camera after γ-ray irradiation mainly comes from the changes in the FWC and spectral response of CIS, and the spectral transmittance of lens. [ABSTRACT FROM AUTHOR]

The electronic and magnetic properties of graphene/MoS2 heterostructures intercalated with 3d transition metal (TM) atoms at different concentrations have been systematically investigated by first principles calculations. The results showed that all the studied systems are thermodynamically stable with large binding energies of about 3.72 eV–6.86 eV. Interestingly, all the TM-intercalated graphene/MoS2 heterostructures are ferromagnetic and their total magnetic moments increase with TM concentration. Furthermore, TM concentration-dependent spin polarization is obtained for the graphene layer and MoS2 layer due to the charge transfer between TM atoms and the layers. A significant band gap is opened for graphene in these TM-intercalated graphene/MoS2 heterostructures (around 0.094 eV–0.37 eV). With the TM concentration increasing, the band gap of graphene is reduced due to the enhanced spin polarization of graphene. Our study suggests a research direction for the manipulation of the properties of 2D materials through control of the intercalation concentration of TM atoms. [ABSTRACT FROM AUTHOR]

The heat flux sensors composed of inclined epitaxial La1−xCaxMnO3 (LCMO) films have been fabricated on c-axis miscut SrTiO3 (001) single crystal substrates. Based on the transverse thermoelectric (TTE) effect originated from the anisotropic Seebeck coefficient between ab-plane and c-axis of LCMO films, the obvious response voltages perpendicular to the temperature gradient are detected, and their amplitudes show good linearity with heat fluxes. The sensitivities of heat flux sensors are 8.64, 11.88, 12.66, and 14.25 μV/(kW/m2) for LCMO films with inclined 12°, 18°, 20°, and 24°, respectively. Additionally, the response frequency of the sensor reaches ∼300 kHz at −3 dB, which is comparable with the reported TTE heat flux sensors composed of YBa2Cu3O7-δ. The above results demonstrate the potential of the LCMO-based TTE heat flux sensors in high-frequency heat flux measurement. [ABSTRACT FROM AUTHOR]

Na3V2(PO4)3 (NVP) is an attractive cathode material for sodium storage because of its NASICON structure with high ionic conductivity and stability. However, its poor electronic conductivity and large volume change have limited its intensive application. Here, we use 1‐butanol as a co‐solvent to synthesize NVP (bNVP) microparticles with a uniform carbon coating layer. We discovered that butanol can effectively improve the graphitization level of the carbon, giving rise to a much higher electronic conductivity compared to the sample synthesized without butanol (pristine NVP, pNVP). As expected, bNVP demonstrates high reversible capacities of 110.3 mAh g−1 at 1 C, superior high‐rate performance of 98 mAh g−1 at 10 C, and enhanced cycling stability of 94 % capacity retention after 3500 cycles at 30 C, which are far better than pNVP, exhibiting great potential for high‐power sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Li4Ti5O12 (LTO), known as a zero-strain material, is widely studied as the anode material for lithium-ion batteries owing to its high safety and long cycling stability. However, its low electronic conductivity and Li diffusion coefficient significantly deteriorate its high-rate performance. In this work, we proposed a facile approach to introduce oxygen vacancies into the commercialized LTO via thermal treatment under Ar/H2 (5%). The oxygen vacancy-containing LTO demonstrates much better performance than the sample before H2 treatment, especially at high current rates. Density functional theory calculation results suggest that increasing oxygen vacancy concentration could enhance the electronic conductivity and lower the diffusion barrier of Li+, giving rise to a fast electrochemical kinetic process and thus improved high-rate performance. [ABSTRACT FROM AUTHOR]

Light and thermal detectors based on the laser-induced transverse voltage (LITV) effect have garnered significant interest for their rapid and broad spectral response. In this study, we prepared the La-doped SrTiO 3 (STO) epitaxial thin films on the 12° inclined single crystal LaAlO 3 (LAO) (100) substrates using our home-designed metal-organic chemical vapor deposition system. Under the illumination of a 248 nm laser, the LITV signals of La x Sr 1- x TiO 3 films were observed and showed dependence on the La doping level, which can be explained by the changes in the light absorption coefficient, thermal conductivity, and optical penetration depth. The optimized LITV signal was observed with a peak voltage of 23.25 V and a decay time of 106 ns under the laser power density of 1.0 mJ mm -2 . The high peak voltage and fast response time of La x Sr 1- x TiO 3 show great potential in the field of light and thermal detection., (© 2024 IOP Publishing Ltd.)