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A series of cross‐linked AEMs (c‐DQPPO/PVA) are synthesized by using rigid polyphenylene oxide and flexible poly(vinyl alcohol) as the backbones. Dual cations are grafted on the PPO backbone to improve the ion exchange capacity (IEC), while glutaraldehyde is introduced to enhance compatibility and reduce swelling ratio of AEMs. In addition to the enhanced mechanical properties resulting from the rigid‐flexible cross‐linked network, c‐DQPPO/PVA AEMs also exhibit impressive ionic conductivity, which can be attributed to their high IEC, good hydrophilicity of PVA, and well‐defined micro‐morphology. Additionally, due to confined dimension behavior and ordered micro‐morphology, c‐DQPPO/PVA AEMs demonstrate excellent chemical stability. Specifically, c‐DQPPO/PVA‐7.5 exhibits a wet‐state tensile strength of 12.5 MPa and an elongation at break of 53.0 % at 25 °C. Its OH− conductivity and swelling degree at 80 °C are measured to be 125.7 mS cm−1 and 8.2 %, respectively, with an IEC of 3.05 mmol g−1. After 30 days in a 1 M NaOH solution at 80 °C, c‐DQPPO/PVA‐7.5 experiences degradation rates of 12.8 % for tensile strength, 27.4 % for elongation at break, 14.7 % for IEC, and 19.2 % for ion conductivity. With its excellent properties, c‐DQPPO/PVA‐7.5 exhibits a peak power density of 0.751 W cm−2 at 60 °C in an H2‐O2 fuel cell. [ABSTRACT FROM AUTHOR]

Preparing AEMs with robust mechanical properties, high ionic conductivity and excellent chemical stability is challenging. Here, cross-linked/aggregated AEMs are prepared by incorporating hydrophilic Jeffamine cross-linkers and hydrophobic side chains into the rigid quaternized poly (vinyl benzyl chloride). Jeffamine's flexibility ensures high elongation at break of the cross-linked/aggregated membranes (125.0–199.8%). The hydrophobic side chain limits excessive water absorption and facilitates self-aggregation of hydrophilic and hydrophobic domains, enhancing tensile strength (5.08–7.40 Mpa in wet state) and improving ionic conductivity of the AEMs (73.8–110.4 mS cm−1 at 80 °C). Alkali-resistant PVB, restricted dimensionality, and ordered micro-phase separation morphology contribute to outstanding chemical stability of the AEMs. Degradation of both backbones and cations is <20% after treatment in 1 M NaOH solution at 80 °C for 30 days. Based on the membrane, a peak power density of 354.4 mW cm−2 at 60 °C is yielded. PVB based AEMs of c (Je) a Cx-QAPVB exhibit excellent flexibility, outstanding alkali-resistant and high hydroxide ion conductivity. [Display omitted] • Highly flexible and transparent poly (vinyl benzyl chloride) based anion exchange membranes are prepared. • Anion exchange membranes exhibit improved ionic conductivity and robust stability. • A peak power density of 354.4 mW cm−2 is presented. [ABSTRACT FROM AUTHOR]

• The CuO/RuO 2 electrode was prepared by the two-step thermal decomposition method for the first time. • Compared with the ordinary RuO 2 electrode, the selectivity of CER of CuO/RuO 2 electrode is remarkably improved. • During the preparation of AEW, the HClO content of AEW2 (prepared by CuO/RuO 2) is 2.5 times that of AEW1 (prepared by RuO 2). • In the sterilization experiments on E. coli and B. subtilis , the germicidal efficacy of AEW2 is obviously superior to that of AEW1. Electrochemical chlorine evolution reaction (CER) is one of the most important practical applications of electrochemical reaction, which can be used for electrochemical disinfection. The electrochemical disinfectant of acidic electrolyzed water (AEW) is obtained by electrolyzing extremely dilute chlorine-containing solution in ion-exchange membrane electrolyzer. In the anode area, HClO is produced by CER, which has a strong bactericidal effect. Due to the low concentration of chloride ion, it is necessary to improve the CER selectivity of the electrode in order to improve the efficiency of chlorine electrolysis. In this paper, CuO/RuO 2 electrode was prepared by the two-step thermal decomposition method, and the surface morphology and electronic structure of RuO 2 electrode were modified. Compared with the ordinary RuO 2 electrode, the CER activity of CuO/RuO 2 electrode is improved. For the oxygen evolution reaction (OER), the activity of CuO/RuO 2 electrode is significantly lower than that of RuO 2 electrode. The CER mechanism of CuO/RuO 2 electrode is the second electron transfer, and the OER mechanism is the formation and transformation of OH ads. The potential difference between CER and OER of CuO/RuO 2 -3 electrode is 105 mV, which is 52 mV higher than that of RuO 2 electrode, so the selectivity of CER of CuO/RuO 2 electrode is remarkably improved. During the preparation of AEW, the HClO of AEW2 (prepared by CuO/RuO 2 -3 electrode) is 0.72 mmol/L, which is 2.5 times that of AEW1 (prepared by RuO 2 electrode). In the sterilization experiments on E. coli and B. subtilis , the germicidal efficacy of AEW2 (3.71 and 2.99 log 10 CFU/mL) is obviously superior to that of AEW1 (0.76 and 0.61 log 10 CFU/mL). [ABSTRACT FROM AUTHOR]

Balancing ion conductivity, mechanical strength, and alkali stability is a significant challenge in the application of anion exchange membranes (AEMs) in anion exchange membrane fuel cells (AEMFCs). In this study, rigid poly(4-vinylbiphenyl chloride) (PVB) and flexible polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) are selected as the polymer backbones to create semi-interpenetrating network (SIPN) AEMs. To achieve high ionic conductivity, quaternary ammonium groups are grafted onto each PVB structural unit, and TMHDA reacts with CMSEBS to construct a cross-linking network while also generating quaternary ammonium groups. This approach, along with well-defined micro-morphology, result in SIPN-SEBS/PVB-10 exhibiting an impressive ionic conductivity of 105.7 mS cm−1 at 80 °C. The SIPN structure, formed by the linear quaternary ammonium PVB and cross-linked SEBS, enhances the compatibility between the rigid and flexible components, resulting in good tensile strength (>14.5 Mpa) and elongation at break (>31.8%) for SIPN-SEBS/PVB AEMs at 25 °C in the wet state. Furthermore, SIPN-SEBS/PVB AEMs exhibit excellent chemical stability, in addition to the restricted swelling behavior, which can be attributed to the stable PVB and SEBS main chains. After immersion in a 1 M NaOH solution at 80 °C for 30 days, the degradation of backbones and cations in all membranes is less than 10% and 20%, respectively. Moreover, the peak power density of SIPN-SEBS/PVB-10 in an H 2 /O 2 single fuel cell reaches an impressive value of 379 mW cm−2. Based on these excellent properties, the developed SIPN AEMs hold great promise as candidates for AEMFCs. Structure diagram and photos of SIPN-SEBS/PVB AEMs. And the single fuel cell performance by using SIPN-SEBS/PVB-10 as the separator. [Display omitted] • A new perspective is offered on the development of AEMs with high performance. • Semi-interpenetrating network AEMs is achieved using linear QPVB and cross-linked c QSEBS. • A peak power density of 379 mW cm−2 is presented. [ABSTRACT FROM AUTHOR]

A series of highly transparent semi-interpenetrating polymer network anion exchange membranes (SIPN AEMs) composed of a flexible and cation cross-linked polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (c QSEBS) component, and a rigid, highly-charged quaternized poly(2,6-dimethyl phenylene oxide) (QPPO) component are prepared. Flexible and rigid polymer backbones endow SIPN AEMs with excellent flexibility and mechanical strength. High charge content and well defined hydrophilic/hydrophobic phase separation patterns ensure SIPN AEMs with improved ionic conductivity. Alkali-resistant SEBS, enhanced dimensional stability and ordered microphase separation morphology contribute to the good chemical stability of SIPN-AEMs. Among these AEMs, SIPN- c QSEBS/QPPO-10 with an IEC of 1.93 mmol g−1 achieves a better trade-off between tensile strength (19.36 MPa at 25 °C in wet state), flexibility (58.43% at 25 °C in wet state) and OH− conductivity (103.1 mS cm−1 at 80 °C). Besides, SIPN- c QSEBS/QPPO-10 shows low swelling degree (15.4% at 80 °C) and high chemical stability (95.9%, 88.7%, 82.7% and 88.5% retention in weight, OH− conductivity, tensile strength and elongation at break, respectively, after immersing in 1 M NaOH at 80 °C for 30 days). Importantly, a fuel cell peak power density of 1.174 W cm−2 is obtained at 80 °C by using SIPN- c QSEBS/QPPO-10 as the separator. Compared with original cross-linked c QSEBS, the semi-interpenetrating network AEM of SIPN- c QSEBS/QPPO-10 exhibits enhanced mechanical properties, improved ionic conductivity and elevated fuel cell performance. [Display omitted] • Highly transparent SIPN AEMs based on PPO and SEBS backbones are prepared. • Good balance achieves among conductivity, mechanical properties and chemical stability. • An AEMFC performance of 1.174 W cm−2 for SIPN- c QSEBS/QPPO-10 is obtained. [ABSTRACT FROM AUTHOR]