More Like this

1. Epitaxial crystals of Bi 2 Pt 2 O 7 pyrochlore through the transformation of δ –Bi 2 O 3 fluorite

   https://doi.org/10.1063/1.4908103  

   Gutiérrez–Llorente, Araceli ; Joress, Howie ; Woll, Arthur ; Holtz, Megan E. ; Ward, Matthew J. ; Sullivan, Matthew C. ; Muller, David A. ; Brock, Joel D. ( March 2015 , APL Materials)
2. A Surface Se‐Substituted LiCo[O 2− δ Se δ ] Cathode with Ultrastable High‐Voltage Cycling in Pouch Full‐Cells

   https://doi.org/10.1002/adma.202005182  

   Zhu, Zhi ; Wang, Hua ; Li, Yao ; Gao, Rui ; Xiao, Xianghui ; Yu, Qipeng ; Wang, Chao ; Waluyo, Iradwikanari ; Ding, Jiaxin ; Hunt, Adrian ; et al ( November 2020 , Advanced Materials)

   Cycling LiCoO₂to above 4.5 V for higher capacity is enticing; however, hybrid O anion‐ and Co cation‐redox (HACR) at high voltages facilitates intrinsic O^α−(α < 2) migration, causing oxygen loss, phase collapse, and electrolyte decomposition that severely degrade the battery cyclability. Hereby, commercial LiCoO₂particles are operando treated with selenium, a well‐known anti‐aging element to capture oxygen‐radicals in the human body, showing an “anti‐aging” effect in high‐voltage battery cycling and successfully stopping the escape of oxygen from LiCoO₂even when the cathode is cycled to 4.62 V. Ab initio calculation and soft X‐ray absorption spectroscopy analysis suggest that during deep charging, the precoated Se will initially substitute some mobile O^α−at the charged LiCoO₂surface, transplanting the pumped charges from O^α−and reducing it back to O²⁻to stabilize the oxygen lattice in prolonged cycling. As a result, the material retains 80% and 77% of its capacity after 450 and 550 cycles under 100 mA g⁻¹in 4.57 V pouch full‐cells matched with a graphite anode and an ultralean electrolyte (2 g Ah⁻¹).

    

   more » « less
3. Free-standing bilayered vanadium oxide films synthesized by liquid exfoliation of chemically preintercalated δ-Li x V 2 O 5 · n H 2 O

   https://doi.org/10.1039/D1MA00085C  

   Houseman, Luke ; Mukherjee, Santanu ; Andris, Ryan ; Zachman, Michael J. ; Pomerantseva, Ekaterina ( April 2021 , Materials Advances)

   null (Ed.)

   A free-standing film composed of bilayered vanadium oxide nanoflakes is for the first time synthesized using a new low-energy process. The precursor powder, δ-Li x V 2 O 5 · n H 2 O, was prepared using a simple sol–gel based chemical preintercalation synthesis procedure. δ-Li x V 2 O 5 · n H 2 O was dispersed and probe sonicated in N -methyl pyrrolidone to exfoliate the bilayers followed by vacuum filtration resulting in the formation of a free-standing film with obsidian color. X-ray diffraction showed lamellar ordering of a single-phase material with a decreased interlayer distance compared to that of the precursor powder. Scanning electron microscopy images demonstrated stacking of the individual nanoflakes. This morphology was further confirmed with scanning transmission electron microscopy that showed highly malleable nanoflakes consisting of ∼10–100 vanadium oxide bilayers. One of the most important consequences of this morphological rearrangement is that the electronic conductivity of the free-standing film, measured by the four-probe method, increased by an order of magnitude compared to conductivity of the pressed pellet made of precursor powder. X-ray photoelectron spectroscopy measurements showed the coexistence of both V 5+ and V 4+ oxidation states in the exfoliated sample, possibly contributing to the change in electronic conductivity. The developed approach provides the ability to maintain the phase purity and crystallographic order during the exfoliation process, coupled with the formation of a free-standing film of enhanced conductivity. The produced bilayered vanadium oxide nanoflakes can be used as the building blocks for the synthesis of versatile two-dimensional heterostructures to create innovative electrodes for electrochemical energy storage applications. 

   more » « less
4. Engineering current density in excess of 200 A mm −2 at 20 T in CORC ® magnet cables containing RE-Ba 2 Cu 3 O 7−δ tapes with 38 μ m thick substrates

   https://doi.org/10.1088/0953-2048/28/12/124001  

   van der Laan, D. C. ; Goodrich, L. F. ; Noyes, P. ; Trociewitz, U. P. ; Godeke, A. ; Abraimov, D. ; Francis, A. ; Larbalestier, D. C. ( October 2015 , Superconductor Science and Technology)
5. LaNi x Fe 1–x O 3−δ as a Robust Redox Catalyst for CO 2 Splitting and Methane Partial Oxidation

   Iftikhar, Sherafghan ; Jiang, Qiongqiong ; Gao, Yunfei ; Liu, Junchen ; Gu, Haiming ; Neal, Luke ; Li, Fanxing ( September 2021 , Energy & Fuels)