Anomalously large interface charge in polarity-switchable photovoltaic devices indicates the large amount of mobile ions in organic–inorganic halide perovskites.

Elastomeric anion exchange membranes (AEMs) were prepared by acid-catalyzed Friedel–Crafts alkylation of the polystyrene block of polystyrene-b-poly­(ethylene-co-butylene)-b-polystyrene (SEBS) using bromoalkylated tertiary alcohols and triflic acid as a catalyst, followed by amination with trimethylamine. This simple one-step bromoalkylation allowed convenient control of both the degree of functionalization and cation tether length by changing the molar ratio and the structure of the bromoalkylated tertiary alcohol. The resulting quaternary ammonium-functionalized ionic triblock SEBS copolymers showed a microphase-separated morphology on the 35 nm length scale. A series of AEMs with different ion exchange capacities and ion tether lengths were systematically investigated by comparing swelling and anion conductivity. Because the SEBS AEMs showed high swelling and low dimensional stability in water due to the rubbery nature of SEBS, the hard segment PS units were cross-linked by 1,6-hexanediamine for practical use. The cross-linking of SEBS AEMs reduced water uptake significantly (e.g., 155% vs 28%) and enhanced their mechanical properties. Because the backbone of the SEBS AEMs are composed of all carbon–carbon bonds, they showed good alkaline stability, preserving their IEC and OH– conductivity after testing in a 1 M NaOH solution at 80 °C for 500 h. Alkaline membrane fuel cell performance was evaluated with the cross-linked SEBS AEM, and a peak power density of 520 mW/cm2 was achieved at 60 °C under H2/O2 conditions.

Electrocatalytic conversion of carbon monoxide (CO) is being actively developed as a key component for tandem CO 2 electrolysis. Signi cant effort has been devoted to engineering CO reduction electrocatalysts for better multi-carbon product selectivity. However, less attention has been paid to other performance parameters, such as liquid product concentration and purity, which are crucial for commercializing CO electrolysis. Here, we present an "internally coupled puri cation" strategy to substantially improve the acetate concentration and purity in CO electrolysis. This improvement was achieved by incorporating both an anode electrocatalyst with high ethanol partial oxidation activity as well as an anion-exchange membrane with high ethanol permeability and good alkaline stability. We have successfully demonstrated stable 120-hour continuous operation of the CO electrolyzer at a xed current density of 200 mA cm − 2 and a full cell potential of < 2.3 V, producing an acetate product stream with a concentration of 1.9 M and a purity of 97.7%. By tuning the reaction conditions, we also showed that the concentration of the acetate production stream can be further increased to 7.6 M while maintaining a purity of > 99%. Additional mechanistic investigation revealed the roles of anode electrocatalysts and anion-exchange membranes in enhancing the acetate selectivity in CO electrolyzers. Finally, a technoeconomic analysis shows that a highly concentrated liquid product stream is essential to reduce the energy consumption associated with the product separation.

Background The regeneration of periodontal bone defect remains a vital clinical challenge. To date, numerous biomaterials have been applied in this field. However, the immune response and vascularity in defect areas may be key factors that are overlooked when assessing the bone regeneration outcomes of biomaterials. Among various regenerative therapies, the up-to-date strategy of in situ tissue engineering stands out, which combined scaffold with specific growth factors that could mimic endogenous regenerative processes. Results Herein, we fabricated a core/shell fibrous scaffold releasing basic fibroblast growth factor (bFGF) and bone morphogenetic protein-2 (BMP-2) in a sequential manner and investigated its immunomodulatory and angiogenic properties during periodontal bone defect restoration. The in situ tissue engineering scaffold (iTE-scaffold) effectively promoted the angiogenesis of periodontal ligament stem cells (PDLSCs) and induced macrophage polarization into pro-healing M2 phenotype to modulate inflammation. The immunomodulatory effect of macrophages could further promote osteogenic differentiation of PDLSCs in vitro. After being implanted into the periodontal bone defect model, the iTE-scaffold presented an anti-inflammatory response, provided adequate blood supply, and eventually facilitated satisfactory periodontal bone regeneration. Conclusions Our results suggested that the iTE-scaffold exerted admirable effects on periodontal bone repair by modulating osteoimmune environment and angiogenic activity. This multifunctional scaffold holds considerable promise for periodontal regenerative medicine and offers guidance on designing functional biomaterials. Graphic Abstract

In this work, a super-assembled framework (SAF) was fabricated to achieve sequential delivery of bFGF and BMP-2 for in situ cementum–ligament–bone complex regeneration.