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Phosphonation and nitrogenation of methyl epoxyoleate (MEO) were done to prepare phosphonitrogenated methyl epoxyoleate (PNMEO). The structural characteristics of PNMEO were characterized. The tribological properties of PNMEO and MEO as additives in a paraffin oil and a rapeseed oil were evaluated, and the morphologies, element compositions and tribochemical species of worn surfaces were analyzed. Results showed that PNMEO was more efficient in enhancing tribological properties of oils than MEO. Results also showed that PNMEO and MEO were more powerful in paraffin oil than in rapeseed oil in improving load-carrying, friction-reducing and anti-wear performances, but in rapeseed oil than in paraffin oil in improving extreme pressure property. The tribological mechanisms of PNMEO in reducing friction and wear were attributed to PNMEO-involved tribo-adsorptions and tribo-reactions to produce a composite boundary lubrication film which consisted of a matrix of PNMEO with inclusions of iron oxide, polyphosphates, aminic compounds, and the base oil molecules. [ABSTRACT FROM AUTHOR]

To improve photoelectrochemical properties of Si nanowires (SiNWs), MoS2/SiNWs is prepared via two-step method. SiNWs is synthesized by metal−catalyzed electroless etching (MCEE) method and MoS2 is subsequently deposited onto SiNWs through the direct thermal decomposition method. MoS2 is introduced as both light absorber and catalyst for hydrogen evolution reaction (HER). Moreover, it forms a heterojunction with SiNWs that contribute to the charge separation. Herein, MoS2/SiNWs attains excellent hydrogen evolution reaction (HER) catalysis with onset potential of 55 mV. A photocurrent density of 25 mA cm− 2 at −1.0 VRHE were achieved under simulated solar illumination, which is about 6 times higher than that of SiNWs, and the carrier concentration is increased by 100−fold. The enhanced photocatalytic activity of MoS2/SiNWs toward HER is attributed to the Schottky junction at the interface, which enhances the photo−generation of electron−hole pairs and suppresses the charge recombination, making them promising earth−abundant alternatives to noble metal−based photocathode for HER. [ABSTRACT FROM AUTHOR]

Nanoscale PtNi/functionalized multiwalled carbon nanotubes (FMWCNTs) catalysts, successfully synthesized by anchoring nickel-platinum alloy nanoparticles on FMWCNTs, are presented in this paper. Compared with conventional commercial Pt/C catalysts, the preliminary results revealed that the PtNi/FMWCNTs catalysts demonstrated not only higher specific activity for oxygen reduction reaction (ORR) but also outstanding stability. The enhancement in the stability of the PtNi/FMWCNTs catalysts is believed to be due to the anchor effects in PtNi alloy structure, the stronger interaction between PtNi alloy nanoparticles and FMWCNTs, and the 'π sites' anchoring centers for metal nanoparticles from CNTs with high graphite. [ABSTRACT FROM AUTHOR]