Broadband near‐infrared (NIR) phosphor‐converted light emitting diode (pc‐LED) is demanded for wearable biosensing devices, but it suffers from low efficiency and low radiance. This study reports a broadband NIR Ca3‐xLuxHf2Al2+xSi1−xO12:Cr3+ garnet phosphor with emission intensity enhanced by 81.5 times. Chemical unit co‐substitution of [Lu3+−Al3+] for [Ca2+−Si4+] is responsible for the luminescence enhancement and further alters the crystal structure and electronic properties of the garnet. Using the optimized phosphor, a NIR pc‐LED with photoelectric efficiencies of 21.28%@10 mA, 15.75%@100 mA and NIR output powers of 46.09 mW@100 mA, 54.29 mW@130 mA is fabricated. The high power NIR light is observed to penetrate upper arms (≈8 cm). For application in NIR spectroscopy, the NIR pc‐LED is used as light source to measure transmission spectra of water, alcohol, and bovine hemoglobin solution. These results indicate the NIR garnet phosphor to be a promising candidate for NIR pc‐LED.

Much attention has been paid to exploring electrode materials with enhanced supercapacitor performance as well as relatively low cost and environmental friendliness. In this work, NiMoO4 nanospheres and nanorods were synthesized by facile hydrothermal methods. The hierarchical NiMoO4 nanospheres were about 2.5 μm in diameter and assembled from thin mesoporous nanosheets with a thickness of about 10-20 nm. The NiMoO4 nanorods were about 80 nm in diameter and about 300 nm to 1 μm in length. Their electrochemical properties were investigated for use as electrode materials for supercapacitors (SCs). The NiMoO4 nanospheres exhibited a higher specific capacitance and better cycling stability and rate capability, which were attributed to their large surface area and high electrical conductivity. The specific capacitances were 974.4, 920.8, 875.5, 859.1, and 821.4 F/g at current densities of 1, 2, 4, 6, and 10 A/g, respectively. Remarkably, the energy density was able to reach 20.1 Wh/kg at a power density of 2100 W/kg. After 2000 cycles, the NiMoO4 nanospheres still displayed a high specific capacitance of about 631.8 F/g at a current density of 5 A/g. These results implied that the hierarchical NiMoO4 nanospheres could be a promising candidate for use as high-performance SCs.

We report the correlated d0 ferromagnetism and photoluminescence in undoped single-crystalline ZnO nanowires synthesized by using a vapor transport method. We systematically tune the oxygen deficiency in the ZnO nanowires from 4% to 20% by adjusting the growth conditions, i.e., selecting different catalyst (Au or Ag) and varying the growth temperature. Our study suggests that oxygen vacancies induce characteristic photoluminescence and significantly boost the room-temperature ferromagnetism. Such undoped ZnO nanowires with tunable magnetic and optical properties are promising to find applications in multifunctional spintronic and photonic nanodevices.

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Efficient coupling solar energy conversion and N 2 fixation by photocatalysis has been shown promising potentials.H owever,t he unsatisfied yield rate of NH 3 curbs its forwarda pplication. Defective typical perovskite,B aTiO 3 , shows remarkable activity under an applied magnetic field for photocatalytic N 2 fixation with an NH 3 yield rate exceeding 1.93 mg L À1 h À1 .T hrough steered surface spin states and oxygen vacancies,t he electromagnetic synergistic effect between the internal electric field and an external magnetic field is stimulated. X-raya bsorption spectroscopya nd density functional theory calculations reveal the regulation of electronic and magnetic properties through manipulation of oxygen vacancies and inducement of Lorentz force and spin selectivity effect. The electromagnetic effect suppresses the recombination of photoexcited carriers in semiconducting nanomaterials, which acts synergistically to promote N 2 adsorption and activation while facilitating fast charge separation under UVvis irradiation.

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