Due to their high specific capacities beyond 250 mAh g-1, lithium-rich oxides have been considered as promising cathodes for the next generation power batteries, bridging the capacity gap between traditional...

Structural and interfacial instability of the LiCoO 2 cathode under a voltage exceeding 4.5 V (vs Li/Li +) severely hinders its practical applications for high-energy-density lithium batteries. Herein, a modified electrolyte with nitriles (suberonitrile or 1,3,6-hexanetricarbonitrile) and fluoroethylene carbonate (FEC) coadditives is demonstrated to form an ultrathin and uniform interface layer on LiCoO 2 cathode under a synergetic effect. As such, LiCoO 2 / Li cells display excellent cyclability at a cutoff voltage of 4.6 V with a capacity retention over 72% after 300 cycles and 60% after 200 cycles at 30 and 55 °C, respectively, even achieving operation at a high current rate (10 C) upon 500 cycles as compared to the controls with fast-falling capacity to zero. Furthermore, an adsorption-coordination mechanism between nitriles and cobalt and synergetic effect of coadditives are explored by the alliance of spectroscopic analysis and theoretical calculations. The contributed lone-pairs on the N 2p orbital of nitriles in coordination lowers the real oxidation state of Co 3+/4+ so that it decreases its catalysis on electrolytes, and the synergy from nitrile-derived species regulates FEC to form an LiF-containing electroninsulated interface layer. This work shares a new insight to nitriles with the synergy of coadditives and paves a way to refine (ultra)high-voltage LiCoO 2 cathode for high-energy-density energy storages.

Background: MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs that regulate gene expression and function, but little is known about regulation of miRNAs in the kidneys under normal or pathologic conditions. Here, we sought to investigate the potential involvement of miRNAs in renal ischemia/reperfusion (I/R) injury and angiogenesis and to define some of the miRNAs possibly associated with renal angiogenesis. Methods and Results: Male Balb/c mice were subjected to a standard renal I/R. CD31 immunostaining indicated a significant increase of microvessels in the ischemic region. VEGF and VEGFR2 expression were increased in renal I/R at both the mRNA and protein levels which were detected by qRT-PCR and Western blot, respectively. More importantly, 76 microRNAs exhibited more than 2-fold changes using Agilent microRNA microarray, which contains downregulation of 40 miRNAs and upregulation of 36 miRNAs. Upregulation of miR-210 was confirmed by qRT-PCR with prominent changes at 4 and 24 h after reperfusion. Furthermore, overexpression of miR-210 in HUVEC-12 cells enhances VEGF and VEGFR2 expression and promotes angiogenesis on Matrigel in vitro. Conclusion: These findings suggest miR-210 may be involved in targeting the VEGF signaling pathway to regulate angiogenesis after renal I/R injury, which provides novel insights into the angiogenesis mechanism of renal I/R injury.

Layered Li-rich Ni, Mn, Co (NMC) oxide cathodes in Li-ion batteries provide high specific capacities (>250 mAh/g) via O-redox at high voltages. However, associated high-voltage interfacial degradation processes require strategies for effective electrode surface passivation. Here, we show that an acidic surface treatment of a Li-rich NMC layered oxide cathode material leads to a substantial suppression of CO 2 and O 2 evolution, 90% and ~100% respectively, during the first charge up to 4.8 V vs. Li +/0. CO 2 suppression is related to Li 2 CO 3 removal as well as effective surface passivation against electrolyte degradation. This treatment does not result in any loss of discharge capacity and provides superior long-term cycling and rate performance compared to as-received, untreated materials. We also quantify the extent of lattice oxygen participation in charge compensation ("O-redox") during Li + removal by a novel ex-situ acid titration. Our results indicate that the peroxo-like species resulting from O-redox originate on the surface at least 300 mV earlier than the activation plateau region around 4.5 V. X-ray photoelectron spectra and Mn-L X-ray absorption spectra of the cathode powders reveal a Li + deficiency and a partial reduction of Mn ions on the surface of the acid-treated material. More interestingly, although the irreversible oxygen evolution is greatly suppressed through the surface treatment, our O K-edge resonant inelastic X-ray scattering shows the lattice O-redox behavior largely sustained. The acidic treatment, therefore, only optimizes the surface of the Li-rich material and almost eliminates the irreversible gas evolution, leading to improved cycling and rate performance. This work therefore presents a simple yet effective approach to passivate cathode surfaces against interfacial instabilities during high-voltage battery operation. File list (2) download file view on ChemRxiv McCloskey_manuscript.pdf (2.13 MiB) download file view on ChemRxiv McCloskey_SuppInfo.pdf (5.91 MiB)

Reversible lattice oxygen reaction, and irreversible oxygen release are clarified in high capacity cation-disordered Li_1.25Nb_0.25Fe_0.50O₂/C cathode for Li-ion batteries.

As a parent compound of Li-rich electrodes, Li 2 MnO 3 exhibits high capacity during the initial charge, however, suffers notoriously low Coulombic efficiency due to irreversible oxygen oxidation and its associated surface activitiesreactions. Here, we successfully optimize tune the oxygen activitiesoxidation process towards reversible oxygen redox reactions by intentionally introducing protons into lithium octahedral vacancies in Li 2 MnO 3 system with its original structural integrity maintained. Combining structural probes, theoretical calculations and resonant inelastic X-ray scattering results, a moderate coupling between the introduced protons and lattice oxygen at the oxidized state is revealed, which stabilizes the oxygen activities in initialduring chargecharging. Such a coupling leads to an unprecedented initial Coulombic efficiency (99.2%) with a further greatly improved discharge capacity of 302 mAh g-1 in the protonated Li 2 MnO 3 electrodes. These findings directly demonstrate an effective concept for controlling oxygen activities in Li-rich cathodessystems, which is critical for developing high-capacity energy cathodes in batteries. TOC GRAPHICS

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Analyses of previous data have confirmed the contribution of the IRF6 gene to susceptibility to nonsyndromic oral clefts (NSOC) in some populations. We tested for associations between the rs2013162, rs2235375, and rs2235371 polymorphisms in IRF6 and the risk of NSOC, using both case-parent trio and case-control designs on samples from western China. Our study group consisted of 332 persons with NSOC, their parents (289 mothers and 243 fathers for 206 complete trios for these three SNPs), and 174 control individuals. We found strong evidence of over-and undertransmission of the C allele (the Val allele) at rs2235371, and the C allele at rs2235375 in cleft caseparent trios (P = 0.013 and P = 0.000, respectively). There were significant differences in the frequency distributions of both genotypes and alleles when cases were compared with control infants at rs2235371 and rs2235375. Five specific haplotypes showed significant over-and undertransmission. These results further support a role for IRF6 variants in western Chinese populations.