Polymerizable Deep Eutectic Solvent-Based Polymer Electrolyte for Advanced Dendrite-Free, High-Rate, and Long-Life Li Metal Batteries.

The recently developed advanced electrolytes possess many crucial qualities, including robust stability, Li dendrite-free, and comparable interface compatibility, for the manufacturing of Li metal batteries with a high energy density. In this study, lithium bis(trifluoromethane)sulfonimide, acrylamide, and succinonitrile were first used to design a polymerizable monomer. Then, it went through in situ thermal polymerization to attain a new solid polymer electrolyte [named poly(PDES)]. The synthesized poly(PDES) electrolyte achieved higher ionic conductivity (∼1.89 × 10-3 S cm-1), oxidation potential (∼5.10 V versus Li+/Li), and a larger lithium-ion transfer number (∼0.63). Moreover, poly(PDES) was nonflammable and could effectively inhibit the formation of Li dendrites. As a result, the assembled batteries using the poly(PDES) electrolyte for both Li||LiFePO4 and Li||LiNi0.8Co0.1Mn0.1O2 exhibited excellent interface compatibility and electrochemical performances. This poly(PDES) electrolyte has promising potential for broad application in lithium-metal batteries with elevated energy density and safety performance in the near future.

Preparation and characterization of vanillin-chitosan Schiff base zinc complex for a novel Zn2+ sustained released system.

In this work, a novel sustained released system (VCSB-Zn(II)) for zinc supplements was built by vanillin-chitosan Schiff base (VCSB) chelated with Zn2+ to improve the zinc trace element utilization ratio. Samples were characterized by FT-IR, 1H NMR, XRD, SEM, and TGA. The results showed that VCSB exhibited a more excellent chelation capacity of Zn2+ than chitosan. The chelation capacity of VCSB was about 1.7 times more than that of chitosan, corresponding to 50.96 mg/g and 29.91 mg/g, respectively. Furthermore, VCSB-Zn(II) showed excellent sustained released performance at simulated gastric fluid because of the acid slow-dissolving ability. And the higher the CN content of VCSB, the higher the cumulative release rate (Ri) of Zn2+, the highest Ri reached 77.81%. The sustained released curves were described by the first-order and Korsmeyer-Peppas equation, which described the Zn2+ sustained released performance caused by the dissolution of VCSB-Zn(II) and Fick diffusion. This Zn2+ sustained released system shows great potential in the application in the field of trace elements supplements for animals.

Assembly of MXene/PP Separator and Its Enhancement for Ni-Rich LiNi0.8Co0.1Mn0.1O2 Electrochemical Performance.

In this work, a few-layer MXene is prepared and sprinkled on a commercial polypropylene (PP) separator by a facile spraying method to enhance the electrochemistry of the Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode. Scanning electron microscope (SEM) and X-ray diffraction (XRD) are used to characterize the morphology and structure of MXene. Fourier transform infrared spectroscopy (FT-IR) and a contact angle tester are used to measure the bond structure and surface wettability PP and MXene/PP separator. The effect of the MXene/PP separator on the electrochemical performance of ternary NCM811 material is tested by an electrochemical workstation. The results show that the two-dimensional MXene material could improve the wettability of the separator to the electrolyte and greatly enhance the electrochemical properties of the NCM811 cathode. During 0.5 C current density cycling, the Li/NCM811 cell with MXene/PP separator remains at 166.2 mAh/g after the 100 cycles with ~90.7% retention. The Rct of MXene/PP cell is measured to be ~28.0 Ω. Combining all analyses results related to MXene/PP separator, the strategy by spraying the MXene on commercial PP is considered as a simple, convenient, and effective way to improve the electrochemical performance of the Ni-rich NCM811 cathode and it is expected to achieve large-scale in high-performance lithium-ion batteries in the near future.

Direct deposition of two-dimensional MXene nanosheets on commercially available filter for fast and efficient dye removal.

Generally, the efficiency of water purification can be greatly increased by a high-flux membrane separation technology. One major challenge in the application of this technology is to achieve high removal efficacy of target pollutants with elevated water flux. Here we report a novel self-assembled composite by depositing two-dimensional MXene nanosheets on a commercialized mixed cellulose ester filter (as designated as MCM). Morphology study reveals that MCM exhibits an ultrathin flaked structure with uniform nanochannels which is stapled on a porous support. The tailored membrane has been successfully applied in the methylene blue solution treatment and 100% ± 0.1% removal rate is achieved while the feed concentration of dye solution is up to 90 mg·L-1. Concurrently, stable and comparatively elevated water flux was achieved, i.e., 28.94 ± 0.74 L·m-2·h-1, which is 1.88-fold of that of the commercialized UTC60 membrane. Further investigations on the separation mechanism are performed to get more insights into separation performance exhibited by MCM. It is found that the size-selective sieving, electrostatic repulsion of MXene and the high porosity of substrate play the synergistic effect on the fast and efficient dye removal behavior. Taken together, the composite membrane fabricated in present work provides an alternatively high-efficiency approach for dye treatment, and unflagging efforts will be further invested on the development and large-scale application of MXene-based membrane.

Effects of Precipitant and pH on Coprecipitation of Nanosized Co-Cr-V Alloy Powders.

Nanosized Co-Cr-V alloy powders were synthesized via coprecipitation method. Effects of precipitants ((NH4)2C2O4·H2O and Na2CO3) and pH were investigated by X-ray diffraction (XRD), Zeta potential analyzer, thermogravimetry-differential scanning calorimetry (TG-DSC), inductively coupled plasma-atomic emission spectrometry (ICP-AES) and scanning electron microscopy (SEM). Co-Cr-V alloy powders were consisted of major face-centered cubic Co (fcc Co) and minor hexagonal close-packed Co (hcp Co). Grain sizes of precursors and Co-Cr-V alloy powders were increased with pH value (7-10) within the ranges of 3~39 and 39~66 nm, respectively. Rod-like or granular Co-Cr-V alloy particles were assembled by interconnected nanograins. At pH = 7, Na2CO3 precipitant was found to be beneficial to maintain the desirable composition of Co-Cr-V powders. It was also found that lower pH favors the maintenance of pre-designed composition, while grain coarsens at higher pH. Effects of variation for precipitant and pH on the morphology and composition of Co-Cr-V alloy powder were discussed in detail and relevant mechanism was further proposed.

Bis(4-amino-pyridinium) tetra-iodido-cad-mate monohydrate.

The title compound, (C(5)H(7)N(2))(2)[CdI(4)]·H(2)O, contains one [CdI(4)](2-) anion, two prontonated 4-amino-pyridine mol-ecules and one water mol-ecule in the asymmetric unit. In the anion, the Cd(II) atom is coordinated by four I atoms in a slightly distorted tetra-hedral geometry. The [CdI(4)](2-) anion and the water mol-ecule are bis-ected by a crystallographic mirror plane perpendicular to the c-axis direction, with the Cd(II) atom, two of the I atoms and the atoms of the water mol-ecule located on this plane. The crystal packing is stabilized by inter-molecular N-H⋯I, N-H⋯O and O-H⋯I hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.798 (3) Å) between pyridine rings, which build up a three-dimensional network.