Interfacial Plasticization Strategy Enabling a Long-Cycle-Life Solid-State Lithium Metal Battery.

The limited ionic conductivity and unstable interface due to poor solid-solid interface pose significant challenges to the stable cycling of solid-state batteries (SSBs). Herein, an interfacial plasticization strategy is proposed by introducing a succinonitrile (SN)-based plastic curing agent into the polyacrylonitrile (PAN)-based composite polymer electrolytes (CPE) interface. The SN at the interface strongly plasticizes the PAN in the CPE, which reduces the crystallinity of the PAN drastically and enables the CPE to obtain a low modulus surface, but it still maintains a high modulus internally. The reduced crystallinity of PAN provides more amorphous regions, which are favorable for Li+ transport. The gradient modulus structure not only ensures intimate interfacial contact but also favors the suppression of Li dendrites growth. Consequently, the interfacial plasticized CPE (SF-CPE) obtains a high ionic conductivity of 4.8 × 10-4 S cm-1 as well as a high Li+ transference number of 0.61. The Li-Li symmetric cell with SF-CPE can cycle for 1000 h at 0.1 mA cm-2, the LiFeO4 (LFP)-Li full-cell demonstrates a high capacity retention of 86.1% after 1000 cycles at 1 C, and the LiCoO2 (LCO)-Li system also exhibits an excellent cycling performance. This work provides a novel strategy for long-life solid-state batteries.

Vitamin E-Oligo(methyl diglycol l-glutamate) as a Biocompatible and Functional Surfactant for Facile Preparation of Active Tumor-Targeting PLGA Nanoparticles.

Poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles have attracted an enormous interest for controlled drug delivery. Their clinical applications are, however, partly hindered by lack of biocompatible, biodegradable and functional surfactants. Here, we designed and developed a novel biocompatible surfactant based on amphiphilic vitamin E-oligo(methyl diglycol l-glutamate) (VEOEG) for facile fabrication of robust and tumor-targeting PLGA-based nanomedicines. VEOEG was prepared with controlled Mn of 1.7-2.6 kg/mol and low molecular weight distribution (D = 1.04-1.16) via polymerization of methyl diglycol l-glutamate N-carboxyanhydride using vitamin E-ethylenediamine derivative (VE-NH2) as an initiator. VEOEG had a hydrophile-lipophile balance data of 13.8-16.1 and critical micellar concentration of 189.3-203.8 mg/L depending on lengths of oligopeptide. Using VEOEG as a surfactant, PLGA nanoparticles could be obtained via nanoprecipitation method with a small and uniform hydrodynamic size of 135 nm and positive surface charge of +26.6 mV, in accordance with presence of amino groups at the surface. The resulting PLGA nanoparticles could be readily coated with hyaluronic acid (HA) to form highly stable, small-sized (143 nm), monodisperse, and negatively charged nanoparticles (HA-PLGA NPs). Notably, paclitaxel-loaded HA-PLGA NPs (PTX-HA-PLGA NPs) exhibited better antitumor effects in CD44-positive MCF-7 breast tumor cells than Taxol (a clinical paclitaxel formulation). The in vivo pharmacokinetics assay in nude mice displayed that PTX-HA-PLGA NPs possessed a long plasma half-life of 3.14 h. The in vivo biodistribution studies revealed that PTX-HA-PLGA NPs had a high tumor PTX level of 8.4% ID/g, about 6 times better than that of Taxol. Interestingly, therapeutic studies showed that PTX-HA-PLGA NPs caused significantly more effective tumor growth inhibition, better survival rate and lower adverse effect than Taxol. VEOEG has emerged as a versatile and functional surfactant for the fabrication of advanced anticancer nanomedicines.

Gradient fluorinated and hierarchical selective adsorption coating for Zn-Based aqueous battery.

Rechargeable aqueous zinc-ion batteries (ZIBs) are considered as one of the most promising large-scale energy storage system due to their high energy density, low cost and inherent safety. However, the notorious dendrite growth and severe side reactions, impede their practical application. Herein, we constructed a multifunctional gradient composite fluorinated coating with insulating ZnF2 outside and Zn/Sn alloy inside. ZnF2 outside and Zn/Sn alloy inside perform their own functions and solve the dendrites and side reactions jointly. Density functional theory (DFT) calculations and Molecular dynamics (MD) simulations demonstrate that the electronically insulating ZnF2 layer on the surface can regulate the transport of Zn2+ cations, limit the free H2O molecules and improve the dissolution of Zn2+, at the same time, the zincophilicity Zn/Sn alloy inside work as the favorable nucleation sites for Zn atoms and lowers the Zn2+ diffusion energy barrier. As a result, the ZnF2-Sn@Zn electrode in a symmetrical cell exhibits a long cycle life of about 1400 h, as well as 91 % capacity retention after 1400 cycles at 1 A/g in the ZnF2-Sn@Zn//MnO2@CNT full batteries. This work provides a practically promising strategy and new insights for the electrolyte and anode interface design.

Surface modification of garnet fillers with a polymeric sacrificial agent enables compatible interfaces of composite solid-state electrolytes.

The poly (vinylidene fluoride) (PVDF)-based composite solid-state electrolyte (CSE) has garnered attention due to its excellent comprehensive performance. However, challenges persist in the structural design and preparation process of the ceramic-filled CSE, as the PVDF-based matrix is susceptible to alkaline conditions and dehydrofluorination, leading to its incompatibility with ceramic fillers and hindering the preparation of solid-state electrolytes. In this study, the mechanism of dehydrofluorination failure of a PVDF-based polymer in the presence of Li2CO3 on the surface of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is analyzed, and an effective strategy is proposed to inhibit the dehydrofluorination failure on the basis of density functional theory (DFT). We introduce a molecule with a small LUMO-HOMO gap as a sacrificial agent, which is able to remove the Li2CO3 impurities. Therefore, the approach of polyacrylic acid (PAA) as a sacrificial agent reduces the degree of dehydrofluorination in the PVDF-based polymer and ensures slurry fluidity, promoting the homogeneous distribution of ceramic fillers in the electrolyte membrane and enhancing compatibility with the polymer. Consequently, the prepared electrolyte membranes exhibit good electrochemical and mechanical properties. The assembled Li-symmetric cell can cycle at 0.1 mA cm-2 for 3500 h. The LiFePO4‖Li cell maintains 91.45% of its initial capacity after 650 cycles at 1C, and the LiCoO2‖Li cell maintains 84.9% of its initial capacity after 160 cycles, demonstrating promising high-voltage performance. This facile modification strategy can effectively improve compatibility issues between the polymer and fillers, which paves the way for the mass production of solid-state electrolytes.

Robust, Responsive, and Targeted PLGA Anticancer Nanomedicines by Combination of Reductively Cleavable Surfactant and Covalent Hyaluronic Acid Coating.

PLGA-based nanomedicines have enormous potential for targeted cancer therapy. To boost their stability, targetability, and intracellular drug release, here we developed novel multifunctional PLGA anticancer nanomedicines by combining a reductively cleavable surfactant (RCS), vitamin E-SS-oligo(methyl diglycol l-glutamate), with covalent hyaluronic acid (HA) coating. Reduction-sensitive HA-coated PLGA nanoparticles (rHPNPs) were obtained with small sizes of 55-61 nm and ζ potentials of -26.7 to -28.8 mV at 18.4-40.3 wt % RSC. rHPNPs were stable against dilution and 10% FBS while destabilized under reductive condition. The release studies revealed significantly accelerated docetaxel (DTX) release in the presence of 10 mM glutathione. DTX-rHPNPs exhibited potent and specific antitumor effect to CD44 + A549 lung cancer cells (IC50 = 0.52 µg DTX equiv/mL). The in vivo studies demonstrated that DTX-rHPNPs had an extended circulation time and greatly enhanced tolerance in mice. Strikingly, DTX-rHPNPs completely inhibited growth of orthotopic human A549-Luc lung tumor in mice, leading to a significantly improved survival rate and reduced adverse effect as compared to free DTX. This study highlights that advanced nanomedicines can be rationally designed by combining functional surfactants and surface coating.

Hyaluronic acid coated PLGA nanoparticulate docetaxel effectively targets and suppresses orthotopic human lung cancer.

PLGA nanotherapeutics though representing a most promising platform for targeted cancer therapy are confronted with low stability and insufficient tumor cell uptake. Here, we report that hyaluronic acid (HA) coated PLGA nanoparticulate docetaxel (DTX-HPLGA) is particularly robust and can effectively target and suppress orthotopic human lung cancer. DTX-HPLGA was easily prepared with a small size of 154nm and negative surface charge of -22.7mV by nanoprecipitation and covalent coating with HA. DTX-HPLGA displayed a low IC50 of 0.91µg/mL in CD44+ A549 cells and a prolonged elimination half-life of 4.13h in nude mice. Interestingly, DTX-HPLGA demonstrated 4.4-fold higher accumulation in the cancerous lung than free DTX, reaching a remarkable level of 13.7%ID/g at 8h post-injection, in orthotopic human A549 lung cancer-bearing mice. Accordingly, DTX-HPLGA exhibited significantly better inhibition of tumor growth than free DTX, leading to healthy mice growth and markedly improved survival time. DTX-HPLGA with easy fabrication, excellent stability and tumor accumulation, effective tumor suppression, and low side effects is of particular interest for targeted chemotherapy of lung cancers.