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Element substitution of BaTiO 3 -based compounds has been demonstrated as a powerful way for designing novel electronic materials (such as polar metals and multiferroics). To trigger magnetism into ferroelectric BaTiO 3 , general substituted elements are magnetic transition metals (such as Mn, Fe, and Co). The doping effect of rare-earth elements (such as Dy) in BaTiO 3 -based compounds was barely investigated. Here, we report the coexistence of magnetism and electric polarization in epitaxial Dy 0.5 Ba 0.5 TiO 3 films. The single-crystalline films were synthesized by high-pressure magnetron sputtering. The crystal and electronic structures were characterized by high-resolution x-ray diffraction, x-ray photoemission spectroscopy, and resonant soft x-ray absorption spectroscopy. Room-temperature electric polarization was demonstrated by optical second-harmonic generation. Temperature-dependent magnetic hysteresis loops were measured to reveal the revolution of magnetism on temperature. Surprisingly, it is uncovered that the Curie temperature of electric-polarized Dy 0.5 Ba 0.5 TiO 3 films is around 100 K, far above the critical temperature of non-polarized DyTiO 3 (near 60 K). Our work provides another view to understand the magnetoelectric materials. [ABSTRACT FROM AUTHOR]

Barium titanate (BaTiO3) is a promising material for silicon-integrated photonics due to its large electro-optical coefficients, low loss, high refractive index, and fast response speed. Several deposition methods have been employed to synthesize BaTiO3 films. Magnetron sputtering is one of these methods, which offers specific advantages for growing large-scale films. However, there is a scarcity of studies investigating the effect of sputtering target density on the quality of BaTiO3 films. Therefore, this study aims to uncover the effect of sputtering targets on the crystal and electronic structures of epitaxial BaTiO3 thin films. Two BaTiO3 ceramic targets were sintered at different densities by altering the sintering temperatures. The crystal structure and chemical composition of the targets were then characterized using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Subsequently, BaTiO3 epitaxial films were grown by magnetron sputtering using these two targets. The crystal and electronic structures of the BaTiO3 films were analyzed using high-resolution X-ray diffraction, X-ray photoemission spectroscopy, atomic force microscopy, and spectroscopic ellipsometry. Notably, the BaTiO3 films grown with high-density targets show superior quality but contain oxygen vacancies, whereas those films synthesized with low-density targets display high surface roughness. These findings provide insights into the effect of sputtering target density on the crystal and electronic structures of epitaxial BaTiO3 thin films. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4), as an attractive metal-free polymer photocatalyst, has attracted extensive attention in energy and environmental fields in recent years. The photoactivity of bulk g-C3N4 is moderate on account of solid-phase thermal-condensation synthesis. This leads to inadequate light absorption, limited surface area, and easy recombination of charge carriers. The composition and nanostructure of g-C3N4 have been studied extensively. Molten-salt modulation is fascinating because of its "green" credentials and the properties of liquid-phase reaction systems. The review focuses mainly on molten-salt modulation of the composition and structure of g-C3N4 based-photocatalysts. We focus on elemental doping, molecular doping, and defect engineering, as well as control of the crystal structure, multi-dimensional structure, hom/heterostructures for photocatalytic applications. This review provides new insights to develop g-C3N4-based photocatalysts with control of composition and structure by facile molten-salt modulation in energy-conversion and environmental fields. [ABSTRACT FROM AUTHOR]

Crystalline carbon dots (CCDs) embedded in carbon nitride (CN) nanofragments (CCDs-CN) have been developed through facile molten salt treatment. Molten salt treatment not only reconstructs CN layered sheets to form nanofragments, but also promotes the crystallization of CDs-CN. The π-conjugated electric field between CCDs and CN accelerates charge carrier separation for efficient photocatalytic H2 evolution. [ABSTRACT FROM AUTHOR]

Unexpected Finding During microsurgery and Potential Risk of Sperm Damage: Intrascrotal Calculi: A Retrospective Analysis Intrascrotal calculi are considered to originate from fibrin, meconium or inflammatory crystal deposits, which are similar to urolithiasis but with an uncertain relationship.[1] Some have reported that intrascrotal calculi are small yellow particles, small chips or larger shapes.2-4 Most of them were irregular, and only some were round pearls.[5] Their main components are carbonate or phosphate.[6] Some studies have found that these intrascrotal calculi lead to a decline in sperm parameters.[7],[8] Other studies also revealed that these interesting things were closely related to testicular tumors.[9] However, due to the low incidence of intrascrotal calculi and the lack of relevant literature, the impact of intrascrotal calculi on sperm is unclear. The lymphocytes and leukocytes of patients with calculi were closely related to the occurrence of calculi, which also proved our judgment. HT

Condensed π-conjugation C-PAN/MS-CN nanotubes were obtained via a facile polyacrylonitrile (PAN)-confined molten salt (MS) thermal condensation of melamine. Carbonized PAN (C-PAN) nanosheets with a conjugate network structure in the molten salt system acted as partition plates confining the thermal condensation of melamine, which promoted the formation of condensed π-conjugation carbon nitride (CN) for the effective charge carrier separation and photocatalytic H2 evolution. [ABSTRACT FROM AUTHOR]

Si, as a narrow bandgap semiconductor with a broadband absorption for sunlight, is considered to be a very competitive photoelectrode material for solar‐driven photoelectrochemical (PEC) water splitting. However, there are major barriers in construction of efficient and stable Si‐based PEC cell, including low photovoltage, sluggish reaction kinetics, and poor stability in electrolytes. This review focuses on the strategies to solve these issues and summarizes recent progress. The working principles of PEC water splitting are first introduced. Then the strategies for improving Si‐based photoelectrode performances are discussed, including (1) the regulation of Si surface morphology for enhancing light harvesting, (2) band structure engineering strategies to reduce recombination of photogenerated carriers, and (3) modification of protection layers for long stability and loading cocatalysts on Si‐based photoelectrodes for accelerating water splitting. Lastly, we have presented some issues of Si‐based photoelectrode materials, which should be addressed in future research. [ABSTRACT FROM AUTHOR]

Generally, photocatalytic reaction efficiency decreases quickly with increasing irradiation intensity. Thus, it is a great challenge to achieve a high reaction efficiency under strong irradiation. Volume photocatalysis (VPs) is a new strategy for improving photocatalytic reaction efficiency. Herein, hierarchically porous polymeric carbon nitride (PCN) U‐PCN‐480 as a novel volume photocatalyst is fabricated by a template‐free pyrolysis of needle‐like urea. It is found for the first time that the hierarchical pore structure endows U‐PCN‐480 with the enhanced photoabsorption ability under strong irradiation. Consequently, Pt/U‐PCN‐480 displays excellent VPs activity for hydrogen evolution in the formic acid reaction system. Notably, the activity and apparent quantum efficiency (AQE) are significantly enhanced with increasing irradiation intensity, and the AQE reaches 62.7% and 70.4% at 400 and 380 nm with the irradiation intensity of 30.5 mW cm−2, respectively, the highest values among the reported data for PCN‐based photocatalysts. This effect of enhanced activity and AQE is the result of the synergy between VPs and the enhanced photoabsorption. The findings offer an approach to resolve the difficult problem of low photocatalytic reaction efficiency under strong irradiation and open a way to develop efficient photocatalyst materials and reaction systems. [ABSTRACT FROM AUTHOR]

Rare-earth nickelates (such as perovskite RNiO3, trilayer R4Ni3O10, and infinite layer RNiO2) have attracted tremendous interest very recently. However, unlike the widely studied RNiO3 and RNiO2 films, the synthesis of trilayer nickelate R4Ni3O10 films is rarely reported. Here, single-crystalline (Nd0.8Sr0.2)4Ni3O10 epitaxial films were coherently grown on SrTiO3 substrates by high-pressure magnetron sputtering. The crystal and electronic structures of (Nd0.8Sr0.2)4Ni3O10 films with oxygen ligand holes were characterized by high-resolution x-ray diffraction, x-ray photoemission spectroscopy, and resonant soft x-ray absorption spectroscopy. The electrical transport measurements reveal a metal–insulator transition behavior near 82 K and negative magnetoresistance in (Nd0.8Sr0.2)4Ni3O10 films. Our work provides a novel route to synthesize high-quality trilayer nickelate R4Ni3O10 films with RNiO3 targets by high-pressure magnetron sputtering. [ABSTRACT FROM AUTHOR]

Realizing ultrathin water and generating an abundant water/air interface in the interconnected pores of photothermal materials is an effective way to boost the solar‐driven water evaporation rate, but still a great challenge. Herein, confinement capillarity (CC) of photothermal thin coating on porous sponge for significantly enhancing the solar‐driven water evaporation is proposed. The thin coating is composed of abundant agminated black/hydrophilic nanoparticles (BHNPs), and the channels among the BHNPs can generate strong capillarity for water transportation. Water can be spontaneously limited and transported among the agminated nanoparticles, rather than fill in the interconnected pores of the sponge. Thus, ultrathin water layer can be realized on the outer/inner surface of the sponge skeleton, without precisely controlling water supply. The thin water layer can not only expose as much evaporation area as possible by increasing the vapor escape channel, but also prevent solar energy to heat excess water. Thanks to the CC, the rate of solar steam generation can be greatly improved. Moreover, the photothermal material with CC can maintain its high evaporation rate during the whole day, and can remove the salt during night time, highlighting its recyclability and anti‐salt‐accumulation property. Moreover, the CC can be readily scaled up for practical applications. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) film is a remarkable material for a variety of applications ranging from superhard coating to superconducting quantum devices, which can be easily oxidized when it works in the atmosphere. However, the study of its oxidation effect on the crystal and electronic structures of epitaxial TiN films is rare as yet. Here, we coherently synthesize TiN epitaxial films on MgO single crystal substrates via reactive magnetron sputtering and, then, dope oxygen into these films via a controllable oxidation process. The crystal and electronic structures are characterized by high-resolution x-ray diffraction, x-ray photoelectron spectra, and Raman spectra. It is revealed that the crystal structure remains to be of the rocksalt type in these films even with heavy oxygen doping. The data of temperature-dependent electrical transport measurements indicate that the superconducting critical temperature (kinetic inductance) decreases (increases) from 4.6 K (0.672 pH/□) in the pristine TiN film to 3.4 K (1.13 pH/□) in the film with a maximum oxygen doping level. Our work provides a controllable way to tune the superconductivity of TiN films, which enables the flexibility to engineer the resultant performance of TiN-based superconducting quantum devices. [ABSTRACT FROM AUTHOR]

Oxygen vacancy plays a key role in the photocatalytic processes of oxide semiconductors. However, it usually needs high hydrogenation temperature to form oxygen vacancy for SrTiO3. To decrease the temperature, Pt was preloaded on SrTiO3 to transform H2 into the active hydrogen through hydrogen spillover. As a result, the surface oxygen vacancy of Pt/SrTiO3‐x forms at low temperature to 150 °C. Without Pt loading, the defects of SrTiO3 cannot occur even at 400 °C. As the hydrogenation temperature increases, the surface oxygen vacancy of Pt/SrTiO3‐x rises, and a thin disorder overlayer on the facet loaded with metal Pt appears at 400 °C; whereas at 600 °C, besides the disorder overlayer, the surface defects at the facets without Pt and bulk defects are produced, indicating the controllable formation of oxygen vacancies. With the increasing of hydrogenation temperature, the activity of Pt/SrTiO3‐x enhances, and reaches the maximum at 400 °C. The produced H2 amount of Pt/SrTiO3‐x prepared at 400 °C is about 3 times as high as that of Pt/SrTiO3. The activity of Pt/SrTiO3‐x obtained at 600 °C is significantly lower than that at 400 °C. The surface oxygen vacancies are responsible for the enhanced activity; while the decreased specific surface and bulk defects produced at high hydrogenation temperature reduce the activity. New method: The method is developed to produce oxygen vacancy for SrTiO3 at low temperature by hydrogen spillover due to photodeposited Pt. The formation of the oxygen vacancies is controllable. The surface oxygen vacancies formed at low temperature promote significantly photocatalytic hydrogen evolution; while the decreased specific surface and bulk defects produced at high hydrogenation temperature reduce the activity. [ABSTRACT FROM AUTHOR]