The exposure of rich active sites is crucial for MoS2 nanocatalysts in efficient hydrogen evolution reaction (HER). However, the active (010) and (100) planes tend to vanish during preparation because of their high surface energy. Employing the protection by thiourea (TU) reactant, a microwave-assisted reactant-protecting strategy is successfully introduced to fabricate active-site-rich MoS2 (AS-rich MoS2). The bifunctionality of TU, as both a reactant and a capping agent, ensures rich interactions for the effective protection and easy exposure of active sites in MoS2, avoiding the complicated control and fussy procedure related to additional surfactants and templates. The as-obtained AS-rich MoS2 presents the superior HER activity characterized by its high current density (j = 68 mA cm(-2) at -300 mV vs RHE), low Tafel slope (53.5 mV dec(-1)) and low onset overpotential (180 mV), which stems from the rich catalytic sites and the promoted conductivity. This work elucidates a feasible way toward high performance catalysts via interface engineering, shedding some light on the development of emerging nanocatalysts.

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Zr80Pt20 alloys may form meta-stable quasicrystals either during devifxification of an amorphous phase or directly upon cooling from a liquid depending on processing conditions. To date, little attention has been given to the role of oxygen on the glass formation or devitrification behavior of Zr-Pt and similar alloys. This study reveals that oxygen content during melt spinning indeed strongly influences the formation of the as-quenched structure. A critical amount of oxygen was found to be required to form amorphous ribbons at a fixed quench rate. At lower oxygen levels (i.e., 4 0 0 ppm mass), a fully crystallized is formed; the structure is composed mainly of meta-stable p-Zr with a small fiaction of a quasicrystalline phase. At higher oxygen levels, the as-quenched structure transitions to a hlly amorphous structure (-1000 pprn mass), and with further oxygen addition forms a mixture of amorphous and quasicrystalline (-1500 ppm mass) or crystalline phases (>2500 pprn mass). Details regarding the structure of the meta-stable p-Zr phase in the low-oxygen ribbons are provided along with a discussion of the structural similarity between this phase and the quasicrystal structure that formed in this alloy.

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