Sodium is a promising anode material for batteries due to its low standard electrode potential, high abundance and low cost. In this work, we report a new rechargeable ~ 3.5 V sodium ion battery using Na anode, amorphous carbon-nanosphere cathode and a starting electrolyte comprised of AlCl 3 in SOCl 2 with uoride-based additives. The battery, exhibiting ultrahigh ~ 2800 mAh/g rst discharge capacity, could cycle with a high reversible capacity up to ~ 1000 mAh/g. Through battery cycling, the electrolyte evolved to contain NaCl, various sulfur and chlorine species that supported anode's Na/Na + redox and cathode's chloride/chlorine redox. Fluoride-rich additives were important in forming a solid-electrolyte interface, affording reversibility of the Na anode for a new class of high capacity secondary Na battery. Main TextDevising new battery concepts is important to meeting society's growing demand of energy storage.Different rechargeable batteries have been developed, including lithium ion batteries (LIBs), sodium ion batteries (SIBs) and aluminum ion batteries (AIBs) [1][2][3][4][5][6][7][8][9] . Prior to the invention of secondary LIBs, a primary Li-metal battery was developed in the 1970's using thionyl chloride (SOCl 2 ) as a catholyte, Li metal as anode and amorphous carbon as the positive electrode [10][11][12][13][14][15][16] . The Li-SOCl 2 battery was attractive due to its high energy density, but did not receive sustained interest due to the lack of rechargeability 17,18 . The battery discharges through Li anode oxidation and catholyte SOCl 2 reduction into sulfur (S), sulfur dioxide (SO 2 ), and chloride ion (Cl -) on the carbon electrode 19,20 . The Clions react with Li + stripped from

Electrocatalytic CO 2 reduction (CO 2 RR) to valuable fuels is a promising approach to mitigate energy and environmental problems, but controlling the reaction pathways and products remains challenging. Here a novel Cu 2 O nanoparticle film was synthesized by square-wave (SW) electrochemical redox cycling of high-purity Cu foils. The cathode afforded up to 98% Faradaic efficiency for electroreduction of CO 2 to nearly pure formate under ≥45 atm CO 2 in bicarbonate catholytes. When this cathode was paired with a newly developed NiFe hydroxide carbonate anode in KOH/borate anolyte, the resulting two-electrode high-pressure electrolysis cell achieved high energy conversion efficiencies of up to 55.8% stably for long-term formate production. While the high-pressure conditions drastically increased the solubility of CO 2 to enhance CO 2 reduction and suppress hydrogen evolution, the (111)-oriented Cu 2 O film was found to be important to afford nearly 100% CO 2 reduction to formate. The results have implications for CO 2 reduction to a single liquid product with high energy conversion efficiency.

Photoluminescence (PL) properties of InN dots embedded in GaN were investigated. We observed a systematic blueshift in the emission energy as the average dot height was reduced. The widely size-tunable emission energy can be ascribed to the size quantization effect. Temperature-dependent PL measurements show that the emission peak energies of the dots are insensitive to temperature, as compared with that of bulk film, indicating the localization of carriers in the dots. A reduced quenching of the PL from the InN dots was also observed, implying superior emission properties for the embedded InN dot structures.

Highly (001)-oriented BiFeO3 ultrathin films of total thickness of less than 10 nm were deposited on Si(001) substrates via deposition of atomic layers (ALD) with a LaNiO3 buffer. A radio-frequency (RF)-sputtered sample of the same thickness was prepared for comparison. The ALD combined with interrupted flow and an exchange reaction between Bi and Fe precursors provides a superior method to grow ternary compounds. According to X-ray diffraction, upon deposition at a temperature of less than 550 °C, the only phase in the film was BiFeO3. Anomalous fine structure from synchrotron X-ray diffraction certified the valence bonding through the BiFeO3 (001) diffraction signal. The stoichiometric ratio of BiFeO3 obtained from X-ray photoelectron spectroscopy indicated that ALD has a proportion much improved over the RF preparation, and this is also in agreement with the results for diffraction anomalous fine structure. The use of high-resolution transmission electron and atomic force microscopes showed that the layer structure and morphology from ALD presented a satisfactory coverage, more conformal than that with the RF method. The BiFeO3 thin film deposited with ALD shows excellent leakage, improved at least 1000 times with respect to the RF preparation, making this method suitable for the fabrication of ferroelectric random-access memory devices. From the hysteresis loop, the largest remanent polarization was observed as 2Pr = 2.0 μC cm(-2).

Local crystal structure, crystal orientation and crystal deformation can all be probed by Laue diffraction using a submicron x-ray beam. This technique, employed at a synchrotron facility is particularly suitable for fast mapping mechanical and microstructural properties of inhomogeneous multi-phase polycrystalline samples as well as imperfect epitaxial films or crystals. As synchrotron Laue X-ray microdiffraction is entering its 20 years of existence and new synchrotron nanoprobe facilities are being built and commissioned around the world, we take the opportunity to give an overview of its current capabilities and latest technical developments. Fast data collection provided by state-of-the-art area detectors and fully automated pattern indexing algorithms optimized for speed make it possible to map large portions of a sample by fine step size and get quantitative images of its microstructure in near real time. Finally, we extrapolate on how the technique will evolve in the near future and its potential emerging application at a free electron laser facility.

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