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1. Electroactive Co( iii ) salen metal complexes and the electrophoretic deposition of their porous organic polymers onto glassy carbon

   https://doi.org/10.1039/C8RA04385J  

   Solomon, Marcello B. ; Rawal, Aditya ; Hook, James M. ; Cohen, Seth M. ; Kubiak, Clifford P. ; Jolliffe, Katrina A. ; D'Alessandro, Deanna M. ( January 2018 , RSC Advances)

   We report the synthesis, characterisation and electrochemistry of Co(iii) salen metal complexes and their porous organic polymers for CO₂electroreduction.
2. Epitaxial Sc _x Al _{1− x} N on GaN exhibits attractive high-K dielectric properties

   https://doi.org/10.1063/5.0075636  

   Casamento, Joseph ; Lee, Hyunjea ; Maeda, Takuya ; Gund, Ved ; Nomoto, Kazuki ; van Deurzen, Len ; Turner, Wesley ; Fay, Patrick ; Mu, Sai ; Van de Walle, Chris G. ; et al ( April 2022 , Applied Physics Letters)

   Epitaxial Sc_xAl_1−xN thin films of ∼100 nm thickness grown on metal polar GaN substrates are found to exhibit significantly enhanced relative dielectric permittivity (ε_r) values relative to AlN. ε_rvalues of ∼17–21 for Sc mole fractions of 17%–25% ( x = 0.17–0.25) measured electrically by capacitance–voltage measurements indicate that Sc_xAl_1−xN has the largest relative dielectric permittivity of any existing nitride material. Since epitaxial Sc_xAl_1−xN layers deposited on GaN also exhibit large polarization discontinuity, the heterojunction can exploit the in situ high-K dielectric property to extend transistor operation for power electronics and high-speed microwave applications.
3. Engineering the interface chemistry for scandium electron contacts in WSe ₂ transistors and diodes

   https://doi.org/10.1088/2053-1583/ab2c44  

   Smyth, Christopher M. ; Walsh, Lee A. ; Bolshakov, Pavel ; Catalano, Massimo ; Schmidt, Michael ; Sheehan, Brendan ; Addou, Rafik ; Wang, Luhua ; Kim, Jiyoung ; Kim, Moon J. ; et al ( July 2019 , 2D Materials)

   Sc has been employed as an electron contact to a number of two-dimensional (2D) materials (e.g. MoS₂, black phosphorous) and has enabled, at times, the lowest electron contact resistance. However, the extremely reactive nature of Sc leads to stringent processing requirements and metastable device performance with no true understanding of how to achieve consistent, high-performance Sc contacts. In this work, WSe₂transistors with impressive subthreshold slope (109 mV dec⁻¹) andI_ON/I_OFF(10⁶) are demonstrated without post-metallization processing by depositing Sc contacts in ultra-high vacuum (UHV) at room temperature (RT). The lowest electron Schottky barrier height (SBH) is achieved by mildly oxidizing the WSe₂in situbefore metallization, which minimizes subsequent reactions between Sc and WSe₂. Post metallization anneals in reducing environments (UHV, forming gas) degrade theI_ON/I_OFFby ~10³and increase the subthreshold slope by a factor of 10. X-ray photoelectron spectroscopy indicates the anneals increase the electron SBH by 0.4–0.5 eV and correspondingly convert 100% of the deposited Sc contacts to intermetallic or scandium oxide. Raman spectroscopy and scanning transmission electron microscopy highlight the highly exothermic reactions between Sc and WSe₂, which consume at least one layer RT and at least three layers after the 400 °C anneals. The observed layer consumption necessitates multiple sacrificial WSe₂layers duringmore »fabrication. Scanning tunneling microscopy/spectroscopy elucidate the enhanced local density of states below the WSe₂Fermi level around individual Sc atoms in the WSe₂lattice, which directly connects the scandium selenide intermetallic with the unexpectedly large electron SBH. The interface chemistry and structural properties are correlated with Sc–WSe₂transistor and diode performance. The recommended combination of processing conditions and steps is provided to facilitate consistent Sc contacts to WSe₂.

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4. The Solar Minimum Eclipse of 2019 July 2. II. The First Absolute Brightness Measurements and MHD Model Predictions of Fe x, xi, and xiv out to 3.4 R _⊙

   https://doi.org/10.3847/1538-4357/ac8101  

   Boe, Benjamin ; Habbal, Shadia ; Downs, Cooper ; Druckmüller, Miloslav ( August 2022 , The Astrophysical Journal)

   We present the spatially resolved absolute brightness of the Fex, Fexi, and Fexivvisible coronal emission lines from 1.08 to 3.4R_⊙, observed during the 2019 July 2 total solar eclipse (TSE). The morphology of the corona was typical of solar minimum, with a dipole field dominance showcased by large polar coronal holes and a broad equatorial streamer belt. The Fexiline is found to be the brightest, followed by Fexand Fexiv(in diskB_⊙units). All lines had brightness variations between streamers and coronal holes, where Fexivexhibited the largest variation. However, Fexremained surprisingly uniform with latitude. The Fe line brightnesses are used to infer the relative ionic abundances and line-of-sight-averaged electron temperature (T_e) throughout the corona, yielding values from 1.25 to 1.4 MK in coronal holes and up to 1.65 MK in the core of streamers. The line brightnesses and inferredT_evalues are then quantitatively compared to the Predictive Science Inc. magnetohydrodynamic model prediction for this TSE. The MHD model predicted the Fe lines rather well in general, while the forward-modeled line ratios slightly underestimated the observationally inferredT_ewithin 5%–10% averaged over the entire corona. Larger discrepancies in the polar coronal holes may point to insufficient heating and/or other limitations in the approach. These comparisons highlightmore »the importance of TSE observations for constraining models of the corona and solar wind formation.

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5. Synthesis and reactivity of a nickel( ii ) thioperoxide complex: demonstration of sulfide-mediated N ₂ O reduction

   https://doi.org/10.1039/C8SC02536C  

   Hartmann, Nathaniel J. ; Wu, Guang ; Hayton, Trevor W. ( January 2018 , Chemical Science)

   The “masked” terminal nickel sulfide [K(18-crown-6)][L^tBuNi^II(S)] mediates the reduction of N₂O by CO,viathe thioperoxide complex [K(18-crown-6)][L^tBuNi^II(η²-SO)].