Molybdenum sulfides are very attractive noble-metal free electrocatalysts for the hydrogen evolution reaction (HER) from water. Atomic structure and identity of the catalytically active sites have been well established for crystalline molybdenum disulfide (c-MoS 2 ) but not for amorphous molybdenum sulfide (a-MoS x ) which displays significantly higher HER activity compared to its

Polyurethane coatings modified with silanized graphene and/or hexagonal boron nitride as nanoadditives were synthesized, characterized, and tested for ultraviolet degradation and hydrophobicity. These coatings containing various weight percentages (wt%) of nanoadditives were prepared and investigated. The coating composition was characterized using Fourier transform infrared spectroscopy. The silanization of nanoadditives was characterized using scanning electron microscopy. The glass transition temperatures (Tg) of the nanocomposite coatings were determined using differential scanning calorimeter; it was observed that the presence of nanoadditives in the coatings impacted the Tg indicating their interference with the polyurethane chains and structures. The change in the coating thickness and water contact angle after ultraviolet light exposure was also studied. Exposure of the coatings to ultraviolet light led to a decrease in the coating thickness and hydrophobicity. With the increasing content of nanoadditives, the decrease in the coating thickness was lower and the rate of decrease of water contact angle was slow. Polyurethane coatings with 0.8 wt% silanized hexagonal boron nitride nanoparticles exhibited minimum reduction in coating thickness and the slowest rate of decrease in the water contact angle.

Combination the materials together is a direct and forceful strategy to improve the electrochemical properties of each raw material. Herein, we present the method of hydrothermal process and treatment/calcination combination that is easy to synthesize a NiCo2O4 nanoparticles‐mesoporous carbon composite (C/NiCo2O4). The result study electrochemical properties of materials revealed that the C/NiCo2O4 composite has excellent electrochemical properties compare with pristine NiCo2O4 or carbon. In particular, maximum specific capacitance of C/NiCo2O4 material at a current density of 1 A.g−1 is 204.28 F.g−1, meanwhile the Cs of carbon and NiCo2O4 are 25.06 F.g−1 and 178.78 F.g−1, respectively. In addition, C/NiCo2O4 material also showed excellent capacitance retention, Cs maintained to 90.35% after 3000 charge‐discharge continuous cycles. The results show that the C/NiCo2O4 is a promising material for application as supercapacitor electrode.

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