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A novel high-performance electrode material, nickel-doped activated mesoporous carbon microsphere (Ni-AMCM), is synthesized by an emulsion-assisted hydrothermal method, followed by a KOH activation process and nickel-doping strategy. The morphology, microstructure, and graphitization degree of Ni-AMCMs are characterized by scanning electron microscopy, nitrogen adsorption and desorption, X-ray diffraction, and Raman spectroscopy. The results show that, when the mass ratio of nickel precursor/AMCMs is 0.02, the resultant sample [denoted as Ni(0.02)-AMCMs] retains the structure parameters of AMCMs, such as the specific surface area, total pore volume, and mean pore size. The intensity ratio of Raman D to G band (I D/I G) decreases from 0.99 (AMCMs) to 0.75 [Ni(0.02)-AMCMs], indicating the formation of a partial graphite structure in Ni(0.02)-AMCMs. The Ni-AMCMs combine the features of high specific surface area (∼1096 m2 g–1), uniform mesopore size (4.0 nm), regular microspherical shape (0.5–1.0 μm in diameter), and partially graphitic structure, which endows them good electrochemical performance. The internal resistance of Ni(0.02)-AMCMs is 0.24 Ω, 43% lower than that of AMCMs (0.42 Ω). Correspondingly, Ni(0.02)-AMCM as an electrode in 6 M KOH shows a specific capacitance of 361 F g–1 at 1.0 A g–1. It still maintains an electrochemical capacitance of 301 F g–1 under a high current density of 20.0 A g–1. This finding is potentially important for supercapacitor applications, where a fast charge/discharge is required.

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The surface species formed from the adsorption of 1,3-butadiene and 1-butene on Mo 2 N/γ-Al 2 O 3 catalyst have been characterized by in situ FT-IR spectroscopy with an attempt to get insight into the selective hydrogenation of 1,3-butadiene on transition metal nitride catalysts. 1,3-Butadiene adsorption on the Mo 2 N/ γ-Al 2 O 3 catalyst forms several kinds of chemisorbed surface species: π-adsorbed butadiene (π s and π d ); σ-bonded species; dehydrogenated species. π s -and σ-bonded butene species are present on the surface for 1-butene adsorption and reaction on the nitride catalyst. The presence of the π d -adsorbed butadiene significantly prevents 1-butene from its adsorption, further hydrogenation, and isomerization on the nitrided catalyst, accordingly resulting in high selectivity in the hydrogenation of 1,3-butadiene to 1-butene. The surface nitrogen atoms weaken the interaction between 1,3-butadiene and the catalyst surface, and result in the high selectivity in the hydrogenation of 1,3-butadiene to 1-butene.