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A series of SrZrO3 : Eu3+ nano phosphors synthesized by a modified high‐temperature solid‐state reaction method. The structural, functional vibration groups, optical, morphological, luminescence and quantum yield studies were characterized through XRD, FTIR, UV, 'SEM & HR‐TEM' and PL analyses respectively. The SrZrO3 : Eu3+ phosphor has a perovskite orthorhombic structure and emits intense red emission around 612 nm when it is excited under 465 nm and covers NUV light range. The calculated average lifetime indicates the nature of the allowed emission transition in Eu3+ (2.44 μs). The calculated colour purity and Commission International del' Eclairagethe (CIE) chromaticity coordinates are 97.9 % and (0.5894, 0.4031) respectively. The observed quantum yield and thermal stability for the SrZrO3 : Eu3+ (9 mol %) phosphor are 22 % and 87 % at 423 K, respectively. These obtained results suggest that SrZrO3 : Eu3+ (9 mol %) phosphor would meliorate for red‐emitting phosphor in profound RGB‐based pc‐WLED applications. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are widely used in applications ranging from electric vehicles to wearable devices. Before the invention of secondary LIBs, the primary lithium-thionyl chloride (Li-SOCl.sub.2) battery was developed in the 1970s using SOCl.sub.2 as the catholyte, lithium metal as the anode and amorphous carbon as the cathode.sup.1-7. This battery discharges by lithium oxidation and catholyte reduction to sulfur, sulfur dioxide and lithium chloride, is well known for its high energy density and is widely used in real-world applications; however, it has not been made rechargeable since its invention.sup.8-13. Here we show that with a highly microporous carbon positive electrode, a starting electrolyte composed of aluminium chloride in SOCl.sub.2 with fluoride-based additives, and either sodium or lithium as the negative electrode, we can produce a rechargeable Na/Cl.sub.2 or Li/Cl.sub.2 battery operating via redox between mainly Cl.sub.2/Cl.sup.- in the micropores of carbon and Na/Na.sup.+ or Li/Li.sup.+ redox on the sodium or lithium metal. The reversible Cl.sub.2/NaCl or Cl.sub.2/LiCl redox in the microporous carbon affords rechargeability at the positive electrode side and the thin alkali-fluoride-doped alkali-chloride solid electrolyte interface stabilizes the negative electrode, both are critical to secondary alkali-metal/Cl.sub.2 batteries. Rechargeable Na/Cl.sub.2 and Li/Cl.sub.2 batteries are produced with a microporous carbon positive electrode, aluminium chloride in thionyl chloride as the electrolyte, and either sodium or lithium as the negative electrode., Author(s): Guanzhou Zhu [sup.1] , Xin Tian [sup.1] , Hung-Chun Tai [sup.2] , Yuan-Yao Li [sup.2] , Jiachen Li [sup.1] , Hao Sun [sup.1] , Peng Liang [sup.1] , Michael [...]

Ti, V, Cr, Mn, Co, and Cu, have been investigated as a third dopant in NiFe sulfide for enhanced oxygen evolution reaction (OER)/oxygen reduction reaction (ORR). The effects of dopant on surface electronic structure, conductivity, and thermodynamic barrier of reaction are addressed and discussed. For the OER, X‐ray photoelectron spectroscopy analysis shows that electron transferring from the Ni to the dopants enhances the catalytic performance of the sulfide. Cu doped NiFe sulfide exhibits the best OER performance. For the ORR, density functional theory calculation indicates that Ti, V, Mn, Co, and Cu upshift the d‐band center (ɛd), while Cr downshifts the ɛd. Among the dopants, V leads to optimized electronic structure modification, giving optimized adsorption energy of *O on the Ni, the lowest rate determining step ΔG1, and the best ORR activity. By considering E10‐E1/2 together with the maximum current density of the OER and limited diffusion current density of the ORR, NiFeVS exhibits the best OER/ORR bifunctionality. The performance of NiFeVS as a cathodic catalyst has also been evaluated in a zinc air battery, demonstrating a specific capacity of 698 mAh g−1, maximum power density of 190 mW cm−2, and a superior cycle stability of 2400 cycles (400 h). [ABSTRACT FROM AUTHOR]

Climate change poses a significant threat to humanity. Achieving net-zero emissions is a key goal in many countries. Among various energy resources, solar power generation is one of the prominent renewable energy sources. Previous studies have demonstrated that post-processing techniques such as bias correction can enhance the accuracy of solar power forecasting based on numerical weather prediction (NWP) models. To improve the post-processing technique, this study proposes a new day-ahead forecasting framework that integrates weather research and forecasting solar (WRF-Solar) irradiances and the total solar power generation measurements for five cities in northern, central, and southern Taiwan. The WRF-Solar irradiances generated by the Taiwan Central Weather Bureau (CWB) were first subjected to bias correction using the decaying average (DA) method. Then, the effectiveness of this correction method was verified, which led to an improvement of 22% in the forecasting capability from the WRF-Solar model. Subsequently, the WRF-Solar irradiances after bias correction using the DA method were utilized as inputs into the transformer model to predict the day-ahead total solar power generation. The experimental results demonstrate that the application of bias-corrected WRF-Solar irradiances enhances the accuracy of day-ahead solar power forecasts by 15% compared with experiments conducted without bias correction. These findings highlight the necessity of correcting numerical weather predictions to improve the accuracy of solar power forecasts. [ABSTRACT FROM AUTHOR]

Abstractα-Fe2O3nanowires (NWs) were formed by the thermal oxidation of an iron film in air at 350 °C for 10 h. The rhombohedral structure of the α-Fe2O3NWs was grown vertically on the substrate with diameters of 8–25 nm and lengths of several hundred nm. It was found that the population density of the NWs per unit area (DNWs) can be varied by the film thickness. The thicker the iron film, the more NWs were grown. The growth mechanism of the NWs is suggested to be a combination effect of the thermal oxidation rate, defects on the film, and selective directional growth. The electrical resistivity of a single NW with a length of 800 nm and a diameter of 15 nm was measured to be 4.42 × 103 Ωcm using conductive atomic force microscopy. The field emission characteristics of the NWs were studied using a two-parallel-plate system. A low turn–on field of 3.3 V/μm and a large current density of 10−3 A/cm2(under an applied field of about 7 V/μm) can be obtained using optimal factors ofDNWsin the cathode.