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This paper reports the chitosan-mediated synthesis of porous hematite nanoparticles with FeCl3 as the precursor via a hydrothermal approach at 160℃.A series of porous chitosan/iron oxide hybrid nanoparticles were obtained via changing the ratio of chitosan to FeCl3,FeCl3 concentration and pH value of the reaction solution,and producing porous iron oxide nanoparticles after calcination.The as-prepared samples were characterized by means of X-ray diffraction,transmission electron microscopy,thermal gravimetric analysis,Fourier transform infrared,and N2 sorption.The particle sizes of these metal oxides were less than 100 nm,and the pore sizes were in the range of 2-16 nm.It was demonstrated that chitosan played a key role in the formation of the porous structures.The resultant α-Fe2O3 nanoparticles were used as the support to immobilize Au or Pd nanoparticles,producing Au/α-Fe2O3 or Pd/α-Fe2O3 nanoparticles.The as-prepared α-Fe2O3 nanocatalyst exhibited high selectivity towards cyclohexanone and cyclohexanol for catalyzing cyclohexane oxidation with O2 at 150℃.
This paper reports the chitosan-mediated synthesis of porous hematite nanoparticles with FeCl3 as the precursor via a hydrothermal approach at 160 ° C. A series of porous chitosan / iron oxide hybrid nanoparticles were obtained by changing the ratio of chitosan to FeCl3, FeCl3 concentration and pH value of the reaction solution, and producing porous iron oxide nanoparticles after calcination. as as prepared samples were characterized by means of X-ray diffraction, transmission electron microscopy, thermal gravimetric analysis, Fourier transform infrared, and N2 sorption.The particle sizes of These metal oxides were less than 100 nm, and the pore sizes were in the range of 2-16 nm. Tit was done that chitosan played a key role in the formation of the porous structures. The resultant α-Fe2O3 nanoparticles were used as the support to immobilize Au or Pd nanoparticles, producing Au / α-Fe2O3 or Pd / α-Fe2O3 nanoparticles. The as-prepared α-Fe2O3 nanocatalyst exhibits high selectivity towards cycl ohexanone and cyclohexanol for catalyzing cyclohexane oxidation with O2 at 150 ° C.