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1. High-Performance Near-IR Photodetector Using Low-Bandgap MA 0.5 FA 0.5 Pb 0.5 Sn 0.5 I 3 Perovskite

   https://doi.org/10.1002/adfm.201701053  

   Xu, Xiaobao ; Chueh, Chu-Chen ; Jing, Peifeng ; Yang, Zhibin ; Shi, Xueliang ; Zhao, Ting ; Lin, Lih Y. ; Jen, Alex K.-Y. ( July 2017 , Advanced Functional Materials)
2. Chemical modification in and on single phase [NiO] 0.5 [Al 2 O 3 ] 0.5 nanopowders produces “chocolate chip‐like” Ni x @[NiO] 0.5‐x [Al 2 O 3 ] 0.5 nanocomposite nanopowders

   https://doi.org/10.1111/jace.16632  

   Wang, Fei ; Sun, Kai ; Yi, Eongyu ; Laine, Richard M. ( June 2019 , Journal of the American Ceramic Society)

   Phase‐pure [NiO]_0.5[Al₂O₃]_0.5spinel nanoparticles (NPs) with limited aggregation were obtained via liquid‐feed flame spray pyrolysis (LF‐FSP) by combusting metalloorganic precursor solutions. Thereafter “chocolate chip‐like” Ni_x[NiO_0.5‐x][Al₂O₃]_0.5nanoparticles consisting of primary [NiO_0.5‐x][Al₂O₃]_0.5particles with average particle sizes of 40‐60 nm decorated with Ni metal particles (<10 nm in diameter) dispersed on the surface were synthesized by heat treating the spinel NPs at 800°C/7 h in flowing 5% H₂:N₂100 mL/min in a fluidized bed reactor. The synthesized materials were characterized using TEM, XRD, FTIR, and TGA/DTA. The Ni depleted areas consist primarily of γ‐Al₂O₃. The Ni content (800°C) was determined by TGA to be ≈11.3 wt.% based on TGA oxidation behavior. The successful synthesis of such nanocomposites with limited aggregation on a high temperature support provides a facile route to synthesize well‐defined NP catalysts. This work serves as a baseline study for an accompanying paper, wherein thin, flexible, dense films made from these same NPs are used as regenerable catalysts for carbon nanotube syntheses.

    

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3. Leveraging Crystallization Pathway to Control Structure in Hf 0.5 Zr 0.5 O 2 Nanoparticles

   https://doi.org/10.1002/adem.202301755  

   Anguish, Evan A. M. ; Andrew, Jennifer S. ( March 2024 , Advanced Engineering Materials)

   Hf_0.5Zr_0.5O₂‐based materials have garnered significant attention for applications requiring ferroelectricity at the nanoscale. This behavior arises due to the stabilization of metastable phases at room temperature. However, the synthesis of phase pure Hf_0.5Zr_0.5O₂remains a challenging problem in both thin films and nanoparticles. Herein, the crystallization of Hf_0.5Zr_0.5O₂nanoparticles from an as‐synthesized amorphous phase is studied. By tailoring the aggregate nature of the intermediate amorphous nanoparticles via different drying processes, the crystallization pathway can be altered, resulting in significant differences in crystal structure, crystallite size, and crystallite morphology after calcination. X‐ray diffraction (XRD) and Rietveld refinement show the dominant crystallographic phase changes from a monoclinic structure to a cubic structure for samples with decreased aggregation. Samples prepared via freeze drying exhibit the most aggregation control and correspond with the observation of single‐crystalline particle aggregates and branching structures attributed to a crystallization by particle attachment mechanism. Herein, differing crystallization pathways lead to unique crystal morphologies that stabilize the traditionally high‐temperature phases of Hf_0.5Zr_0.5O₂‐based materials that are necessary for functional applications.

    

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4. Electronic band structure and magnetism of CoFeV 0.5 Mn 0.5 Si

   https://doi.org/10.1063/9.0000252  

   Kharel, Parashu ; Baker, Gavin ; Flesche, Matthew ; Ramker, Adam ; Moua, Young ; Valloppilly, Shah ; Shand, Paul M. ; Lukashev, Pavel V. ( March 2022 , AIP Advances)

   Half-metallic Heusler alloys have attracted significant attention due to their potential application in spin-transport-based devices. We have synthesized one such alloy, CoFeV 0.5 Mn 0.5 Si, using arc melting and high-vacuum annealing at 600 °C for 24 hours. First principles calculation indicates that CoFeV 0.5 Mn 0.5 Si shows a nearly half-metallic band structure with a degree of spin polarization of about 93%. In addition, this value can be enhanced by the application of tensile strain. The room temperature x-ray diffraction patterns are indexed with the cubic crystal structure without secondary phases. The annealed sample shows ferromagnetic order with the Curie temperature well above room temperature ( T c = 657 K) and a saturation magnetization of about 92 emu/g. Our results indicate that CoFeV 0.5 Mn 0.5 Si has a potential for room temperature spin-transport-based devices. 

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5. Superhard W 0.5 Ta 0.5 B nanowires prepared at ambient pressure

   https://doi.org/10.1063/1.4967447  

   Yeung, Michael T. ; Akopov, Georgiy ; Lin, Cheng-Wei ; King, Daniel J. ; Li, Rebecca L. ; Sobell, Zachary C. ; Mohammadi, Reza ; Kaner, Richard B. ( November 2016 , Applied Physics Letters)