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The development of highly active electrocatalysts is essential to the commercialization of water splitting. Introducing ligand of foreign metals is a promising approach to optimize the electronic structure of electrocatalyst and regulate chemisorption behavior of intermediate species.Herein, Ru(OH) x Cl y cluster−modified CoNi alloy nanoparticles encapsulated in nitrogen-doped graphene (Ru-CoNi@NC-X) was prepared by a partial galvanic replacement method. The electrochemical results indicated that a moderated Ru(OH) x Cl y cluster was beneficial to improve the both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) properties of CoNi alloy nanoparticles (CoNi@NC).

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Optimizing the surface structure at the atomic scale is crucial for developing effective catalysts. In this work, a hybrid material consisting of well-dispersed sub-nanometer-sized (SNS) iridium (Ir) species decorated on mesoporous Co 3 O 4 was fabricated as electrocatalyst for the oxygen evolution reaction (OER) through pyrolysis of IrCl 3 /Co(NO 3 ) 2 complexes confined within the mesoporous KIT-6 template. It was found that the KIT-6 template played a critical role in the formation of SNS Ir species. The optimized IrÀ Co 3 O 4 -1 showed highly efficient OER catalytic performance with an overpotential of 1.527 V to achieve the current density of 10 mA cm À 2 , and superior stability in alkaline condition. The electrochemical results demonstrated that moderate Ir incorporation was conductive to form the high valence Co ions in form of Co oxyhydroxide during the OER process. The present work would open a new route for material design of SNS Ir species decorated mesoporous metal oxides for the application in catalysis.

Unraveling the effect of metal doping on the intrinsic activity of metal nitride remains a grand challenge. Herein, Ru (Rh)‐doped vanadium nitride are successfully synthesized via a simple soft‐urea pathway. In comparison, the Ru‐doped VN electrocatalyst exhibits much better HER performance than Rh‐doped VN electrocatalysts. The optimal Ru‐VN catalyst delivers a low overpotential of 134 (144) mV at current density of 10 mA cm−2, and a low Tafel slope of 35 (73) mV dec−1 in acidic (alkaline) condition. Such excellent performance can be attributed to the unique synergetic effect between Ru and VN. Moreover, moderate Ru dopant can effectively promote the HER kinetics of VN, resulting in mechanism transformation of hydrogen evolution from Volmer‐Heyrovsky to Volmer‐Tafel route, especially in acidic condition. This simple and facile strategy can be utilized to fabricate a series of Ru‐doped nitrides, which can be applied in energy conversion fields.

Vanadium oxides are promising cathode materials for rechargeable aqueous zinc-ion batteries (RAZIBs). However, the selfagglomeration and poor ion/electron conductivity of vanadium oxides in the charge/discharge process usually lead to low capacity and capacity attenuation, which limits their commercial application. Herein, we report a facile and mass-production method for fabricating 3D porous carbon/water-pillared V 2 O 5 nanosheet composites with sandwich structure (PC/V 2 O 5 • nH 2 O), which can further reduce the preparation cost of vanadiumoxide-based cathodes. Moreover, the excellent structural characteristics of PC/V 2 O 5 • nH 2 O not only effectively inhibits the aggregation and stacking of V 2 O 5 • nH 2 O but also increases the contact area between the active substance and the electrolyte, which is conducive to the transport of zinc ions and improves the electrochemical performance of RAZIBs. The PC/V 2 O 5 • nH 2 O cathode displays an excellent rate performance (325.3 mAh g À 1 at high current density 20 A g À 1 ), a high specific discharge capacity of 415.4 mAh g À 1 at 0.5 A g À 1 , an outstanding cyclic stability, and capacity retention (after 1000 cycles the capacity retention rate about 97.1 %). Ex situ XRD patterns reveal that the charge/discharge process of the PC/V 2 O 5 • nH 2 O electrode undergoes a reversible intercalation and conversion process. The method used in this work provides an idea for large-scale synthesis of vanadium-based cathode materials for multivalent batteries.

Stable superhydrophobic surface based on low‐density polyethylene (LDPE)/ethylene–propylene–diene terpolymer (EPDM) thermoplastic vulcanizate (TPV) was successfully fabricated by using etched aluminum foil as template. The etched aluminum template consisted of micropores and step‐like textures, was obtained by the metallographic sandpaper sanding and the subsequent acid etching. The surface morphology and hydrophobic properties of the series molded TPV surfaces were researched by varying the weight ratio of the LDPE/EPDM TPV. The superhydrophobic LDPE/EPDM TPV surfaces exhibited the microstructures consisting of step‐like textures obtained via molding with etched aluminum template and a large number of fiber‐like structures resulted from the plastic deformation of LDPE matrix. The obtained TPV (LDPE/EPDM weight ratio = 70/30) surface exhibited the remarkable superhydrophobicity, with a contact angle of 152.0° ± 0.7° and a sliding angle of 3.1° ± 0.8°. The molded TPV surface had excellent environmental stability when the pH of water solution was in the range of 1 to 14; moreover, the surface also showed the excellent resistance to various organic solvents. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46241.

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