Followed by decades of successful efforts in developing cathode materials for high specific capacity lithium-ion batteries, currently the attention is on developing a high-voltage battery (>5 V vs Li/Li+) with an aim to increase the energy density for their many fold advantages over conventional <4 V batteries. Among the various cathode materials, phosphate polyanion materials (LiMPO4, where M is a single metal or a combination of metals) showed promising candidacy given their high electrochemical potential (4.8–5 V vs Li/Li+), long cycle stability, low cost, and achieved specific capacity (∼165 mAh·g–1) near to its theoretical limit (170 mAh·g–1). In this review, factors affecting the electrochemical potential of the cathode materials are reviewed and discussed. Techniques to improve the electrical and ionic conductivities of phosphate polyanion cathodes, namely, surface coating, particle size reduction, doping, and morphology engineering, are also discussed. A processing–property correlation in phosphate polyanion materials is also undertaken to understand relative merits and drawbacks of diverse processing techniques to deliver a material with targeted functionality. Strategies required for high-voltage phosphate polyanion cathode materials are envisioned, which are expected to deliver lithium-ion battery cathodes with higher working potential and gravimetric specific capacity.

The vinyl radical (C2H3)Ã 2A″←X̃ 2A′ spectrum has been measured between 530 and 385 nm using cavity-ringdown spectroscopy. The active vibrational progressions involve C–C stretching and alpha H–C–C bending vibrations. Optimal rotational constants and linewidths were determined for the first four vibrational bands by modeling the spectrum as an asymmetric top. The best-fit rotational constants obtained for the excited electronic state are consistent with the molecular geometry predicted by ab initio calculations. The lifetime of the vibrationless level in the excited electronic state is estimated to be a few picoseconds, and increasing vibrational excitation leads to a decrease in the lifetime, based upon an increasing linewidth. Various possibilities for the predissociation mechanism are discussed. The most likely is judged to be a conical intersection or seam of intersections. A preliminary CASSCF calculation has found the point on the relevant potential energy surfaces at which the ground and electronically excited states are closest. While the geometry and other properties of this crossing point are in accord with the experimental results, the calculated position of the point of closest approach of the two electronic states lies considerably (&gt;1 eV, including zero-point energy) above the already predissociative Ã 2A″ state origin. Other mechanisms are also discussed to account for the observed rapid predissociation. Clearly there is a need for a higher level theoretical work on this problem.

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In this study, we used a solution-casting technique to prepare all-solid-state composite polymer electrolytes (CPEs) based on poly(vinyl alcohol)/polyacrylonitrile blends, the ceramic filler Li 1.4 Al 0.4 Ti 1.6 (PO 4 ) 3 (LATP, NASICON-type structure), lithium bis-(trifluoromethanesulfonyl)imide, and the solid plasticizer succinonitrile (SN) and then investigated their electrochemical stability, ionic transport properties, and interfacial behavior against lithium electrodes. The CPEs prepared with optimal concentrations of LATP (20 wt %) and SN (10 wt %) exhibited a maximum ionic conductivity of 1.13 × 10 −4 S cm −1 at 25 °C, a Li + -ion transference number of 0.507, and an electrochemical stability window of 5.1 V (vs Li/Li + ). This CPE was a free-standing membrane and highly flexible. An all-solid-state Li//LiFePO 4 battery assembled with this CPE displayed excellent cycling stability and rate performance at room temperature. A maximum discharge capacity of 159.6 mA h g −1 was achieved at 0.1C. The full cell achieved a discharge capacity of 119.4 mA h g −1 at 0.5C and a capacity retention of 90.5% after 100 cycles at ambient temperature. Therefore, this as-prepared CPE shows great promise for use in all-solidstate lithium-metal batteries.

Although solid-state Li-metal batteries (LMBs) featuring polymer-based solid electrolytes might one day replace conventional Li-ion batteries, the poor Li-ion conductivity of solid polymer electrolytes at low temperatures has hindered their practical applications. Herein, we describe the first example of using a co-precipitation method in a Taylor flow reactor to produce the metal hydroxides of both the Ga/F dual-doped Li7La3Zr2O12 (Ga/F-LLZO) ceramic electrolyte precursors and the Li2MoO4-modified Ni0.8Co0.1Mn0.1O2 (LMO@T-LNCM 811) cathode materials for LMBs. The Li/Nafion (LiNf)-coated Ga/F-LLZO (LiNf@Ga/F-LLZO) ceramic filler was finely dispersed in the poly­(vinylidene fluoride)/polyacrylonitrile/lithium bis­(trifluoromethanesulfonimide)/succinonitrile matrix to give a trilayer composite polymer electrolyte (denoted “Tri-CPE”) through a simple solution-casting. The bulk ionic conductivity of the Tri-CPE at room temperature was approximately 4.50 × 10–4 S cm–1 and exhibited a high Li+ ion transference number (0.84). It also exhibits a broader electrochemical window of 1–5.04 V versus Li/Li+. A full cell based on a CR2032 coin cell containing the LMO@T-LNCM811-based composite cathode, when cycled under 1 C/1 C at room temperature for 300 cycles, achieved an average Columbic efficiency of 99.4% and a capacity retention of 89.8%. This novel fabrication strategy for Tri-CPE structures has potential applications in the preparation of highly safe high-voltage cathodes for solid-state LMBs.

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Sonodynamic therapy is an effective treatment for eliminating tumor cells by irradiating sonosentitizer in a patient’s body with higher penetration ultrasound and inducing the free radicals. Titanium dioxide has attracted the most attention due to its properties among many nanosensitizers. Hence, in this study, carbon doped titanium dioxide, one of inorganic materials, is applied to avoid the foregoing, and furthermore, carbon doped titanium dioxide is used to generate ROS under ultrasound irradiation to eliminate tumor cells. Spherical carbon doped titanium dioxide nanoparticles are synthesized by the sol-gel process. The forming of C-Ti-O bond may also induce defects in lattice which would be beneficial for the phenomenon of sonoluminescence to improve the effectiveness of sonodynamic therapy. By dint of DCFDA, WST-1, LDH and the Live/Dead test, carbon doped titanium dioxide nanoparticles are shown to be a biocompatible material which may induce ROS radicals to suppress the proliferation of 4T1 breast cancer cells under ultrasound treatment. From in vivo study, carbon doped titanium dioxide nanoparticles activated by ultrasound may inhibit the growth of the 4T1 tumor, and it showed a significant difference between sonodynamic therapy (SDT) and the other groups on the seventh day of the treatment.

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