摘要
OMS-2 nanorod catalysts were synthesized by a hydrothermal redox reaction method using Mn SO4(OMS-2-SO4) and Mn(CH3COO)2(OMS-2-AC) as precursors. SO4^2--doped OMS-2-AC catalysts with different SO4^2-concentrations were prepared next by adding(NH4)2SO4solution into OMS-2-AC samples to investigate the effect of the anion SO4^2-on the OMS-2-AC catalyst. All catalysts were then tested for the catalytic oxidation of ethanol. The OMS-2-SO4 catalyst synthesized demonstrated much better activity than OMS-2-AC. The SO4^2-doping greatly influenced the activity of the OMS-2-AC catalyst, with a dramatic promotion of activity for suitable concentration of SO4^2-(SO4/catalyst = 0.5% W/W). The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS),inductively coupled plasma optical emission spectroscopy(ICP-OES), NH3-TPD and H2-TPR techniques. The results showed that the presence of a suitable amount of SO4^2-species in the OMS-2-AC catalyst could decrease the Mn–O bond strength and also enhance the lattice oxygen and acid site concentrations, which then effectively promoted the catalytic activity of OMS-2-AC toward ethanol oxidation. Thus it was confirmed that the better catalytic performance of OMS-2-SO4 compared to OMS-2-AC is due to the presence of some residual SO4^2-species in OMS-2-SO4 samples.
OMS-2 nanorod catalysts were synthesized by a hydrothermal redox reaction method using Mn SO4(OMS-2-SO4) and Mn(CH3COO)2(OMS-2-AC) as precursors. SO4^2--doped OMS-2-AC catalysts with different SO4^2-concentrations were prepared next by adding(NH4)2SO4solution into OMS-2-AC samples to investigate the effect of the anion SO4^2-on the OMS-2-AC catalyst. All catalysts were then tested for the catalytic oxidation of ethanol. The OMS-2-SO4 catalyst synthesized demonstrated much better activity than OMS-2-AC. The SO4^2-doping greatly influenced the activity of the OMS-2-AC catalyst, with a dramatic promotion of activity for suitable concentration of SO4^2-(SO4/catalyst = 0.5% W/W). The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS),inductively coupled plasma optical emission spectroscopy(ICP-OES), NH3-TPD and H2-TPR techniques. The results showed that the presence of a suitable amount of SO4^2-species in the OMS-2-AC catalyst could decrease the Mn–O bond strength and also enhance the lattice oxygen and acid site concentrations, which then effectively promoted the catalytic activity of OMS-2-AC toward ethanol oxidation. Thus it was confirmed that the better catalytic performance of OMS-2-SO4 compared to OMS-2-AC is due to the presence of some residual SO4^2-species in OMS-2-SO4 samples.
基金
financially supported by the National Natural Science Foundation of China (No. 21422706)
the Program of the Ministry of Science and Technology of China (No. 2012AA062702)