Different oxygen and nitrogen containing functional groups were created on the surface of the multiwalled carbon nanotubes. The multi-walled carbon nanotubes were treated in ultrasonic bath with sulfuric or nitric aci...Different oxygen and nitrogen containing functional groups were created on the surface of the multiwalled carbon nanotubes. The multi-walled carbon nanotubes were treated in ultrasonic bath with sulfuric or nitric acid. Furthermore the surface texture was modified by increase of the roughness. In particular after treatment with the oxidizing nitric acid, in comparison to the H2SO4 or ultra-sonic treated samples,craters and edges are dominating the surface structures. Manganese oxide was deposited on the multiwalled carbon nanotubes by precipitation mechanism. Various manganese oxides are formed during the deposition process. The samples were characterized by elemental analysis, microscopy, thermal analysis,Raman spectroscopy, and by the zeta potential as well as X-ray diffraction measurements. It was shown that the deposited manganese oxides are stabilized rather by surface texture of the multi-walled carbon nanotubes than by created functional groups.展开更多
Colloidal solution combustion synthesis(CSCS)is a simple and easy method for mass-production of crystalline nanomaterials with tunable pore structure.In this work,mesoporous Mn/CeO_(2) catalysts were fabricated via CS...Colloidal solution combustion synthesis(CSCS)is a simple and easy method for mass-production of crystalline nanomaterials with tunable pore structure.In this work,mesoporous Mn/CeO_(2) catalysts were fabricated via CSCS method coupled with a dip-coating process and used for photocatalytic oxidation(PCO)of toluene.Under vacuum ultraviolet(VUV)irradiation,a high toluene removal efficiency of about 92%was achieved with a toluene reaction rate of about 118μmol/g/h in a continuous flow reactor.A possible degradation pathway was proposed based on the analysis of intermediates by Fourier transform infrared photoluminescence spectra(FTIR)and GC-Mass.Hydrogen temperature-programmed reduction(H_(2)-TPR),Brunauer-Emmett-Teller(BET)surface areas,photoluminescence spectra(PL)spectra and X-ray photoelectron spectroscopy(XPS)were carried out to analyze physical and chemical properties of the catalysts.Compared with Mn_(x)Ce_(1-x)O_(2) catalysts synthesized by one step CSCS method,Mn/CeO_(2) has a higher photocatalytic activity,which is attributed to the presence of higher contents of Ce^(3+),Mn^(2+)and Mn^(3+)species.The presence of higher contents of these species plays a key role in the activity enhancement of toluene oxidation and ozone decomposition.This method is facile,efficient and scalable,and it may become a promising industrial application technology for catalyst synthesis in the near future.展开更多
文摘Different oxygen and nitrogen containing functional groups were created on the surface of the multiwalled carbon nanotubes. The multi-walled carbon nanotubes were treated in ultrasonic bath with sulfuric or nitric acid. Furthermore the surface texture was modified by increase of the roughness. In particular after treatment with the oxidizing nitric acid, in comparison to the H2SO4 or ultra-sonic treated samples,craters and edges are dominating the surface structures. Manganese oxide was deposited on the multiwalled carbon nanotubes by precipitation mechanism. Various manganese oxides are formed during the deposition process. The samples were characterized by elemental analysis, microscopy, thermal analysis,Raman spectroscopy, and by the zeta potential as well as X-ray diffraction measurements. It was shown that the deposited manganese oxides are stabilized rather by surface texture of the multi-walled carbon nanotubes than by created functional groups.
基金supported by an international collaboration funding of China Petrochemical Technology Company Limited。
文摘Colloidal solution combustion synthesis(CSCS)is a simple and easy method for mass-production of crystalline nanomaterials with tunable pore structure.In this work,mesoporous Mn/CeO_(2) catalysts were fabricated via CSCS method coupled with a dip-coating process and used for photocatalytic oxidation(PCO)of toluene.Under vacuum ultraviolet(VUV)irradiation,a high toluene removal efficiency of about 92%was achieved with a toluene reaction rate of about 118μmol/g/h in a continuous flow reactor.A possible degradation pathway was proposed based on the analysis of intermediates by Fourier transform infrared photoluminescence spectra(FTIR)and GC-Mass.Hydrogen temperature-programmed reduction(H_(2)-TPR),Brunauer-Emmett-Teller(BET)surface areas,photoluminescence spectra(PL)spectra and X-ray photoelectron spectroscopy(XPS)were carried out to analyze physical and chemical properties of the catalysts.Compared with Mn_(x)Ce_(1-x)O_(2) catalysts synthesized by one step CSCS method,Mn/CeO_(2) has a higher photocatalytic activity,which is attributed to the presence of higher contents of Ce^(3+),Mn^(2+)and Mn^(3+)species.The presence of higher contents of these species plays a key role in the activity enhancement of toluene oxidation and ozone decomposition.This method is facile,efficient and scalable,and it may become a promising industrial application technology for catalyst synthesis in the near future.
