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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]

Electrolyzing water is an environmentally friendly and renewable way to obtain high purity hydrogen. Ruthenium has strong water dissociation ability and suitable hydrogen adsorption energy, so it is considered as one of the candidates of excellent electrocatalysts for hydrogen evolution in alkaline solution. The dynamic hydrogen bubble template (DHBT) is a good electrodeposition technology, which can obtain the 3D metal foams. However, as far as we know, there is no report on the preparation of Ru electrocatalyst by the DBHT method. In this work, the trumpet-shaped Ru on amorphous cobalt support (T-Ru/a-Co) is prepared by the DHBT electrodeposition for the first time. The defect locations are uniformly distributed on the surface of amorphous cobalt (a-Co), which can effectively lead to the formation of nano-bubble template in the DHBT process. However, this special morphology cannot be obtained on the surface of crystalline Co (c-Co). In addition, the electronic structure of T-Ru/a-Co has also been obviously modified, in which the proportion of Ru4+/Ru0 in T-Ru/a-Co has increased, accompanied by the change of binding energy of Ru. It only needs an overpotential of 49 mV to obtain a current density of 10 mA cm−2 for the T-Ru/a-Co. The specific activity (SA), turnover frequency (TOF) and mass activity (MA) of T-Ru/a-Co are 0.23 mA cm−2, 0.48 s−1 and 0.24 A mg−1, which are both higher than those of Pt/C, the disk-shaped Ru on the c-Co support (D-Ru/c-Co) and Ru/C, respectively. • The trumpet-shaped Ru is prepared by the dynamic hydrogen bubble template (DHBT) electrodeposition for the first time. • The amorphous Co can form nano-bubble template in DHBT process, but it can't be realized on the surface of crystalline Co. • The electronic structure of trumpet-shaped Ru has also been obviously modified. • The specific activity, turnover frequency and mass activity of trumpet-shaped Ru are both higher than those of Pt/C. [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]

The Z-scheme photocatalysts of WO 3 /g-C 3 N 4 composites with WO 3 nanoplates anchored on the surface of g-C 3 N 4 were synthesized by in-situ acidic precipitation and following calcination procedure. The resultant photocatalysts were characterized by various analytical techniques. This face-to-face intimate contact between g-C 3 N 4 and plate-like WO 3 not only increases the interfacial contact areas, but also facilitates the transfer and separation of photogenerated charge carriers. The photocatalytic activities of degradation Rhodamine (RhB) solution over WO 3 /g-C 3 N 4 composites were evaluated under visible light irradiation. The enhanced photocatalytic activity of WO 3 /g-C 3 N 4 composite could be attributed to the formation of the Z-scheme heterojunction system based on the active species trapping and hydroxyl radicals photoluminescence (PL) detection experiments. Furthermore, electrochemical impedance spectroscopy (EIS) and transient photocurrent measurements confirm the more efficient separation and transfer of photogenerated charge carriers on the WO 3 /g-C 3 N 4 composite than that of pure WO 3 or g-C 3 N 4 . This work would provide new insights into the design and preparation of face-to-face contact heterojunction photocatalysts for organic contaminant removal. [ABSTRACT FROM AUTHOR]

The MoS 2 /ZnIn 2 S 4 composites with MoS 2 anchored on the surface of ZnIn 2 S 4 microspheres were fabricated by a facile solvothermal method. To clarify the crystal phases, morphologies, chemical compositions, optical properties, and special surface areas of the obtained photocatalysts, the corresponding characterization measurements were performed. The photocatalytic H 2 evolution activities of MoS 2 /ZnIn 2 S 4 composites were evaluated and compared with using lactic acid as sacrificial reagents. The results showed that integrating MoS 2 with ZnIn 2 S 4 could remarkably boost the photocatalytic H 2 evolution performance and the maximum H 2 evolution rate of 201 μmol h −1 was achieved over 1 wt% MoS 2 loading on the ZnIn 2 S 4 , corresponding to the apparent quantum efficiency (AQE) about 3.08% at 420 nm monochromatic light. The photoelectrochemical tests and photoluminescence spectra (PL) versified that the efficient charge transfer and separation were achieved over MoS 2 /ZnIn 2 S 4 composite in contrast with single ZnIn 2 S 4 , which would significantly benefit the enhancement of photocatalytic H 2 activity. This work provides a desired strategy to design and synthesize the visible-light-response photocatalysts with MoS 2 as cocatalysts to enhance the photocatalytic activity. [ABSTRACT FROM AUTHOR]

The MoS 2 /CdS composites with layered MoS 2 loaded on uniform CdS nanospheres were synthesized by a two-step process combination hydrothermal and solvothermal treatments, and then applied in photocatalytic hydrogen evolution under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Raman spectra, UV–vis diffuse reflectance absorption spectra (UV-DRS), nitrogen adsorption-desorption measurement, photoluminescence spectra (PL) and photoelectrochemical tests. The effects of loading contents of MoS 2 in the composites on the photocatalytic H 2 evolution activity were comparatively investigated with 0.45 mol L −1 Na 2 S and 0.55 mol L −1 Na 2 SO 3 as sacrificial agents. The results showed that the 5 wt% MoS 2 /CdS composite could achieve the highest photocatalytic H 2 evolution rate of 372 μmol h −1 and apparent quantum efficiency (AQE) about 7.31% under 420 nm monochromatic light irradiation. The remarkably enhanced photocatalytic activity of MoS 2 /CdS composite could be attributed to the effective transfer and separation of photogenerated charge carriers, and MoS 2 being as a cocatalyst to facilitating photocatalytic H 2 evolution reaction. A tentative mechanism of MoS 2 /CdS composites as photocatalysts for H 2 evolution was proposed. [ABSTRACT FROM AUTHOR]

In order to achieve a better trade-off among ionic conductivity, mechanical strength and chemical stability, a series of novel aggregated and ionic cross-linked anion exchange membranes (AEMs) are recommended, namely, ac S 6 QAPSF, ac S 8 QAPSF and ac S 10 QAPSF. Cross-linked network shoulders the responsibility to toughen the ac S x QAPSF. Appropriate micro-morphology is responsible for facilitating the conduction of OH− and improving the alkaline stability of the ac S x QAPSF. Compared with the original QAPSF, ac S x QAPSF membranes exhibit much better properties. Specifically, for ac S 8 QAPSF, a high OH− conductivity of 90.5 mS cm−1 is achieved at 80 °C, with the swelling degree of 10.0%. The tensile strength and elongation at break of wet ac S 8 QAPSF at 25 °C are 23.9 Mpa and 21.1%, respectively. After testing in 1 M NaOH at 80 °C for 30 days, the weight loss of ac S 8 QAPSF is 8.0%, with the losses of tensile strength and elongation at break of 13.8% and 13.3%, respectively. Its IEC and IC retentions are 92.0% and 90.5%, respectively. For ac S 8 QAPSF, a fuel cell peak power density of 0.612 W cm−2 is obtained at 60 °C. While for QAPSF, its fuel cell peak power density is only 0.101 W cm−2, and the film is cracked after the 30 days stability test. The unique ac S x QAPSF membrane can alleviate the tradeoff among ionic conductivity, mechanical strength and chemical stability. Image 1 • Novel aggregated and ionic cross-linked AEMs based on PSF are synthesized. • An important insight into the design of AEMs with high performance is provided. • The fuel cell of ac S 8 QAPSF achieved a peak power density of 612 mW cm−2 at 60 °C. [ABSTRACT FROM AUTHOR]