A Gel Polymer Electrolyte with 2D Filler-reinforced for Dendrite Suppression Li-Ion Batteries

Gel polymer electrolytes (GPEs) incorporate both the high ionic conductivity of organic liquid electrolyte and the high safety performance of all-solid-state electrolytes (ASSEs), greatly improving the electrochemical performance of solid polymer electrolytes (SPEs). However, the practical application of GPEs is still limited by inferior interface compatibility, lithium dendrites, etc. Herein, we prepared GPEs based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) further co-blended the two-dimensional sheet inorganic filler hectorite and poly(methyl methacrylate) (PMMA) to improve the mechanical and electrochemical properties of the GPEs. When the content of PMMA and hectorite is optimal, this GPEs have an ionic conductivity of 1.06×10⁻³ S cm⁻¹ and outstanding lithium symmetric cells cycle time of more than 3000 h, indicating that the introduction of filler effectively inhibits the growth of lithium dendrites at room temperature. Moreover, the GPEs adopt a relatively simple solution casting method to provide a fresh idea for the synthesis of high-performance GPEs.     

pH-temperature Responsive Hydrogel-Mediated Delivery of Exendin-4 Encapsulated Chitosan Nanospheres for Sustained Therapeutic Efficacy in Type 2 Diabetes Mellitus

Type 2 Diabetes Mellitus (T2D) is a chronic, obesity-related, and inflammatory disorder characterize by insulin resistance, inadequate insulin secretion, hyperglycemia, and excessive glucagon secretion. Exendin-4 (EX), a clinically established antidiabetic medication that acts as a glucagon-like peptide-1 receptor agonist, is effective in lowering glucose levels and stimulating insulin secretion while significantly reducing hunger. However, the requirement for multiple daily injections due to EX's short half-life is a significant limitation in its clinical application, leading to high treatment costs and patient inconvenience. To address this issue, an injectable hydrogel system is developed that can provide sustained EX release at the injection site, reducing the need for daily injections. In this study, the electrospray technique is examine to form EX@CS nanospheres by electrostatic interaction between cationic chitosan (CS) and negatively charged EX. These nanospheres are uniformly dispersed in a pH-temperature responsive pentablock copolymer, which forms micelles and undergoes sol-to-gel transition at physiological conditions. Following injection, the hydrogel gradually degraded, exhibiting excellent biocompatibility. The EX@CS nanospheres are subsequently released, maintaining therapeutic levels for over 72 h compared to free EX solution. The findings demonstrate that the pH-temperature responsive hydrogel system containing EX@CS nanospheres can be a promising platform for the treatment of T2D.     

Sulfone-based high-voltage electrolytes for high energy density rechargeable lithium batteries:Progress and perspective

Further enhancement in the energy density of rechargeable lithium batteries calls for high-voltage cathode materials and stable anodes,as well as matched high-voltage electrolytes without compromising the overall property of batteries.Sulfone-based electrolytes have aroused great interest in recent years owing to their wide electrochemical window and high safety.However,significant challenges such as the complexity of synthesis,high melting point(typically above room temperature),high viscosity,and their poor compatibility with graphite-based anodes have drastically impeded their practical applications.In this review,recent progress of sulfone solvents in high energy density rechargeable lithium batteries is summarized theoretically and experimentally.More importantly,general improvement methods of sulfone-based electrolytes,such as adding additives and cosolvents,structural modifications of sulfo ne,superconcentrated salt strategy are briefly discussed.We expect that this review provides inspiration for the future developments of sulfone-based high-voltage electrolytes(SHVEs) and their widespread applications in high specific energy lithium batteries.     

Preparation of safe water–lipid mixed electrolytes for application in ion capacitor

Aqueous electrolytes are safe, economic, and environmentally friendly. However, they have a narrow potential window. On the other hand, organic electrolytes exhibit good thermodynamic stability but are inflammable and moisture sensitive. In this study, we prepared water–PEG–lipid ternary electrolytes(TEs). To combine the advantages of water, polyethylene glycol(PEG) and propylene carbonate(PC). The nonflammable mixed electrolytes exhibited a wide potential window of about 2.8 V due to the beneficial effects of PEG and PC. Using these TEs, a lithium manganate–active carbon ion capacitor could be operated at 2.4 V with an energy density of 32 Wh/kg, based on the total active electrode material(current density of 3.3 m A/cm~2). This value was significantly higher than that achieved using an aqueous electrolyte, thereby rationalizing the higher energy density.     

Self-assembled lamellar nanochannels in polyoxometalate-polymer nanocomposites for proton conduction

The construction of nanostructured ion-transport channels is highly desirable in the design of advanced electrolyte materials,as it can enhance ion conductivity by offering short ion-transport pathways.In this work,we present a supramolecular strategy to fabricate a nanocomposite electrolyte containing highly ordered lamellar proton-conducting nanochannels,by the electrostatic self-assembly of a polyoxometalate H_3 PW_(12)O_(4 O)(PW) and a comb copolymer poly(4-methlstyrene)-graft-poly(N-vinyl pyrrolidone).PW can effectively regulate the self-assembling order of polymer moieties to form a large-ra nge lamellar structure,meanwhile,introducing protons into the nanoscale lamellar domains to build proton transport channels.Moreover,the rigid PW clusters contribute a remarkable mechanical reinforcement to the nanocomposites.The lamellar nanocomposite exhibits a conductivity of 4.3 × 10~(-4) S/cm and a storage modulus of 1.1 × 10~7 Pa at room temperature.This study provides a new strategy to construct nanostructured ion-conductive pathways in electrolyte materials.     

Advanced Surfaces by Anchoring Thin Hydrogel Layers of Functional Polymers

Surface design and engineering is a critical tool to improve the interaction of materials with their surroundings. Immobilization of soft hydrogels is one of the attractive strategies to achieve surface modification. The goal of this review is to provide a comprehensive overview of the different strategies used for surface tethering of hydrogel layers via crosslinking immobilization of pre-fabricated functional polymers. In this strategy, crosslinkable polymers are first prepared via various polymerization techniques or post-functionalization of polymers. Afterwards, the crosslinkable polymers are attached or tethered on the surfaces of substrates using a variety of approaches including photo-crosslinking, click reactions, reversible linkages, etc. For each case, the principles of hydrogel tethering have been explained in detail with representative examples.Moreover, the potential applications of the as-modified substrates in specific cases have also been addressed and overviewed.     

DNA水凝胶在生物传感中的应用和发展

脱氧核糖核酸(DNA)是一种重要的生物分子,具有许多独特的性质如:信息传递、分子识别、可编辑等.DNA水凝胶同时具有DNA分子和水凝胶材料的优势,并且可以引入其他纳米材料获得多功能杂化水凝胶.相比于传统水凝胶,DNA水凝胶具有良好的特异识别能力以及可以按需设计的性质,从而被广泛应用于生物传感领域.本文围绕DNA水凝胶的...     

MOFs/水凝胶复合材料的制备及其应用研究

金属有机框架(MOFs)具有大量的孔隙结构和活性位点,在气体吸附、催化、医疗等领域均发挥了巨大的作用。MOFs是晶体粉末,具有脆性较大、在水中易分解和不易回收等缺点,从而限制了其应用。通过MOFs与柔性高分子的复合,特别是与水凝胶的复合,极大地改善了复合材料的柔顺性、可回收和可加工性等特性,进一步拓宽了MOFs的应用领域。本文详细阐述了基于水凝胶MOFs原位生成法、MOFs /水凝胶同时生成法和水凝胶包裹MOFs法等三种不同方法制备MOFs/水凝胶复合材料的研究进展,并对上述三种制备方法的特点及其产物特征进行了总结,进一步归纳了复合材料在生物医药、催化、废水处理和气体吸附等领域的应用。最后,对MOFs/水凝胶复合材料制备方法的改进和复合材料应用前景进行了深入讨论和展望。     

Characterization of a Multi-responsive Magnetic Graphene Oxide Nanocomposite Hydrogel and Its Application for DOX Delivery

Nanocomposite hydrogels are one of the most important types of biomaterials which can be used in many different applications such as drug delivery and tissue engineering.Incorporation of nanoparticles within a hydrogel matrix can provide unique characteristics like remote stimulate and improved mechanical strength.In this study,the synthesis of graphene oxide and graphene oxide nanocomposite hydrogel has been studied.Nanocomposite hydrogel was synthesized using carboxymethyl cellulose as a natural base,acrylic acid as a comonomer,graphene oxide as a filler,ammonium persulfate as an initiator,and iron nanoparticles as a crosslinking agent.The effect of reaction variables such as the iron nanoparticles,graphene oxide,ammonium persulfate,and acrylic acid were examined to achieve a hydrogel with maximum absorbency.Doxorubicin,an anti-cancer chemotherapy drug,was loaded into this hydrogel and its release behaviors were examined in the phosphate buffer solutions with different pH values.The structure of the graphene oxide and the optimized hydrogel were confirmed by Fourier-transform infrared spectroscopy,Raman spectroscopy,X-ray diffraction,scanning electron microscopy,and atomic force microscopy.