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1. Phase Stabilized MOCVD Growth of β‐Ga ₂ O ₃ Using SiO _x on c‐Plane Sapphire and AlN/Sapphire Template

   https://doi.org/10.1002/pssa.202300036  

   Jewel, Mohi Uddin; Hasan, Samiul; Crittenden, Scott R.; Avrutin, Vitaliy; Özgür, Ümit; Morkoç, Hadis; Ahmad, Iftikhar (April 2023, physica status solidi (a))

   The growth of monoclinic phase‐pure gallium oxide (β‐Ga₂O₃) layers by metal–organic chemical vapor deposition on c‐plane sapphire and aluminum nitride (AlN) templates using silicon‐oxygen bonding (SiO_x) as a phase stabilizer is reported. The β‐Ga₂O₃layers are grown using triethylgallium, oxygen, and silane for gallium, oxygen, and silicon precursors, respectively, at 700 °C, with and without silane flow in the process. The samples grown on sapphire with SiO_xphase stabilization show a notable change from samples without phase stabilization in the roughness and resistivity, from 16.2 to 4.2 nm and from 85.82 to 135.64 Ω cm, respectively. X‐ray diffraction reveals a pure‐monoclinic phase, and Raman spatial mapping exhibits higher tensile strain in the films in the presence of SiO_x. The β‐Ga₂O₃layers grown on an AlN template, using the same processes as for sapphire, show an excellent epitaxial relationship between β‐Ga₂O₃and AlN and have a significant change in β‐Ga₂O₃surface morphology. 

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2. Selective Catalytic Combustion of Hydrogen under Aerobic Conditions on Na ₂ WO ₄ /SiO ₂

   https://doi.org/10.1002/anie.202412932  

   Kipp, Elijah R; Garcia‐Barriocanal, Javier; Bhan, Aditya (December 2024, Angewandte Chemie International Edition)

   Abstract Na₂WO₄/SiO₂, a material known to catalyze alkane selective oxidation including the oxidative coupling of methane (OCM), is demonstrated to catalyze selective hydrogen combustion (SHC) with >97 % selectivity in mixtures with several hydrocarbons (CH₄, C₂H₆, C₂H₄, C₃H₆, C₆H₆) in the presence of gas‐phase dioxygen at 883–983 K. Hydrogen combustion rates exhibit a near‐first‐order dependence on H₂partial pressure and are zero‐order in H₂O and O₂partial pressures. Mechanistic studies at 923 K using isotopically‐labeled reagents demonstrate the kinetic relevance of H−H dissociation and absence of O‐atom recombination. In situ X‐ray diffraction (XRD) and W L_III‐edge X‐ray absorption spectroscopy (XAS) studies demonstrate, respectively, a loss of Na₂WO₄crystallinity and lack of second‐shell coordination with respect to W⁶⁺cations below 923 K; benchmark experiments show that alkali cations must be present for the material to be selective for hydrogen combustion, but that materials containing Na alone have much lower combustion rates (per gram Na) than those containing Na and W. These data suggest a synergy between Na and W in a disordered phase at temperatures below the bulk melting point of Na₂WO₄(971 K) during SHC catalysis. The Na₂WO₄/SiO₂SHC catalyst maintains stable combustion rates at temperatures ca. 100 K higher than redox‐active SHC catalysts and could potentially enable enhanced olefin yields in tandem operation of reactors combining alkane dehydrogenation with SHC processes. 

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3. Heavy-Ion-Induced Displacement Damage Effects on WO _x ECRAM

   https://doi.org/10.1109/TNS.2024.3360409  

   Marinella, Matthew J.; Bennett, Christopher H.; Zutter, Brian; Siath, Max; Spear, Matthew; Vizkelethy, Gyorgy; Xiao, T. Patrick; Fuller, Elliot; Hughart, David; Agarwal, Sapan; et al (April 2024, IEEE Transactions on Nuclear Science)
4. MOCVD Epitaxy of Ultrawide Bandgap β-(Al _x Ga _1–x ) ₂ O ₃ with High-Al Composition on (100) β-Ga ₂ O ₃ Substrates

   https://doi.org/10.1021/acs.cgd.0c00864  

   Anhar Uddin Bhuiyan, A F; Feng, Zixuan; Johnson, Jared M.; Huang, Hsien-Lien; Hwang, Jinwoo; Zhao, Hongping (October 2020, Crystal Growth & Design)

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5. Band offsets of (100) β -(Al _x Ga _1−x ) ₂ O ₃ / β -Ga ₂ O ₃ heterointerfaces grown via MOCVD

   https://doi.org/10.1063/5.0031584  

   Bhuiyan, A F; Feng, Zixuan; Johnson, Jared M.; Huang, Hsien-Lien; Hwang, Jinwoo; Zhao, Hongping (December 2020, Applied Physics Letters)

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