Preparation and Study of Multi-Heteroatom Carbon Nanotube as Excellent Electrocatalyst for Oxygen Reduction Reaction Using Polydopamine Derivative

F and other heteroatom codoped multiwalled carbon nanotubes as nonmetal electrocatalyst were developed through pyrolysis of polydopamine derivative under high temperature. The influence of the amount and type of heteroatom on the catalytic activity was investigated. Especially, N/S/F-codoped carbon nanotubes exhibit the most excellent electrocatalytic activity for oxygen reduction reaction and stability. The method afforded an excellent building block to universally design multi-heteroatom-doped or F-doped carbon materials for ORR or other energy-relevant applications

Ordered mesoporous zirconium oxophosphate supported tungsten oxide solid acid catalysts: the improved Bronsted acidity for benzylation of anisole

A series of WO3 supported on ordered mesoporous zirconium oxophosphate (X wt% WO3/M-ZrPO) solid acid catalysts with a WO3 loading from 5 to 30 wt% were successfully synthesized, and their structure properties were characterized by X-ray diffraction (XRD), Raman spectroscopy, N-2-physisorption, transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, H-2 temperature-programmed reduction (H-2-TPR) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of X wt% WO3/M-ZrPO in liquid phase benzylation of anisole was studied and the relation between activity and states of tungsten species was investigated detailedly. The maximum catalytic activity was reached at a 20 wt% WO3 loading, which possessed highly dispersed WO3 species and the strongest Bronsted acidity. Meanwhile, the well dispersed WO3 species strongly interacted with M-ZrPO, therefore, both sintering and leaching of WO3 species were effectively restrained. Moreover, compared with the traditional zirconium phosphate synthesized from the sol-gel method (ZrPsol-gel), the M-ZrPO with an abundant ordered mesostructure was propitious for improving the dispersion of WO3 species and catalytic performance. In addition, the 20 wt% WO3/M-ZrPO showed a markedly higher catalytic activity than H-ZSM5, H-Beta and 20 wt% WO3/ZrPsol-gel. Furthermore, the catalyst showed no discernible loss in activity or selectivity after five cycles

One-pot synthesis of mesoporous ZrPW solid acid catalyst for liquid phase benzylation of anisole

Mesoporous zirconium phosphotungstate (M-ZrPW), with large specific surface area (similar to 170 m(2) g(-1)), large pore volume (similar to 0.25 cm(3) g(-1)), uniform pore size distribution (similar to 6.5 nm) and tunable W/Zr ratios (0-0.2), was successfully prepared via a facile one-pot evaporation-induced self-assembly (EISA) strategy. Small-angle X-ray diffraction (SXRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) characterizations showed that these materials had a mesoporous structure even when the W/Zr ratio reached up to 0.2. The tungsten species introduced via this strategy highly were dispersed among the wall of mesoporous framework. More importantly, the tungsten species greatly improved the Bronsted acidic property and catalytic activity in the Friedel-Crafts benzylation reaction. The highest activity was obtained at a W/Zr ratio of 0.2 with the strongest Bronsted acidity. In addition, the influences of various reaction parameters such as reaction time, amount of catalyst and calcination temperature of the catalyst, systematically investigated in this paper. Furthermore, the M-ZrPW showed a higher catalytic activity than H-Beta, H-ZSM5 and ZrPW prepared by the sol-gel method. Meanwhile, M-ZrPW could be reused at least for five cycles in the benzylation reaction without any notable decrease of catalytic activity