Mesostructured Co3O4-CeO2 composite was found to be an effective catalytic material for the complete oxidation of benzene. The Co3O4-CeO2 catalysts with different Co/Ce ratios (mol/mol) were prepared via the nanocas...Mesostructured Co3O4-CeO2 composite was found to be an effective catalytic material for the complete oxidation of benzene. The Co3O4-CeO2 catalysts with different Co/Ce ratios (mol/mol) were prepared via the nanocasting method and the mesostructure was replicated from two-dimensional (2D) hexagonal SBA-15 and three-dimensional (3D) cubic KIT-6 silicas, respectively. All the obtained Co3O4-CeO2 catalysts exhibited the similar symmetry with the parent silicas and well ordered mesostructures. The Co3O4- CeO2 catalysts with 2D mesostructure showed lower catalytic activities than the corresponding 3D materials. The Co3O4-CeO2 catalyst nanocasted from KIT-6 and with the Co/Ce ratio of 16/1 possessed the best catalytic benzene oxidation activity due to larger quantities of surface hydroxyl groups and surface oxygenated species. The mesostructured Co3O4-CeO2 material thus shows great potential as a promising eco-environmental catalyst for benzene effective elimination.展开更多
CeO2-Co3O4 catalysts for low-temperature CO oxidation were prepared by a co-precipitation method. In combination with the characterization methods of N2 adsorption/desorption, XRD, temperature-programmed reduction (...CeO2-Co3O4 catalysts for low-temperature CO oxidation were prepared by a co-precipitation method. In combination with the characterization methods of N2 adsorption/desorption, XRD, temperature-programmed reduction (TPR), and FT-IR, the influence of the cerium content on the catalytic performance of CeO2-Co3O4 was investigated. The results indicate that the prepared CeO2-Co3O4 catalysts exhibit a better activity than that of pure CeO2 or pure Co3O4. The catalyst with the Ce/Co atomic ratio 1 : 16 exhibits the best activity, which converts 77% of CO at room temperature and completely oxidizes CO at 45 ℃.展开更多
Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 na...Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 nano-particles herein by using flower stem as biotemplate. The resulting samples were characterized by field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM), Raman spectra, X-ray diffraction spectroscopy(XRD), nitrogen adsorption and desorption, X-ray photoelectron spectrogram(XPS), and electrochemical test. The 3D graphene acted as an excellent carrier together with Co_3O_4-CeO_2 nano-particles, boosting the specific capacitance of composite(221 F/g), which exceeded the theoretical value limit. This facile biotemplate method of research provided an eco-friendly and cut-price route to obtain high-quality graphene and Co_3O_4-CeO_2nano-composites owing to the unique porous structure derived from original template(flower stem). The finding presented a simple strategy for fabrication of novel energy storage devices.展开更多
基金supported by the National Natural Science Funds for Distinguished Young Scholar (No.20725723)the National Basic Research Program of China(No. 2010CB732300)the National High Technology Research and Development Program of China (No.2006AA06A310)
文摘Mesostructured Co3O4-CeO2 composite was found to be an effective catalytic material for the complete oxidation of benzene. The Co3O4-CeO2 catalysts with different Co/Ce ratios (mol/mol) were prepared via the nanocasting method and the mesostructure was replicated from two-dimensional (2D) hexagonal SBA-15 and three-dimensional (3D) cubic KIT-6 silicas, respectively. All the obtained Co3O4-CeO2 catalysts exhibited the similar symmetry with the parent silicas and well ordered mesostructures. The Co3O4- CeO2 catalysts with 2D mesostructure showed lower catalytic activities than the corresponding 3D materials. The Co3O4-CeO2 catalyst nanocasted from KIT-6 and with the Co/Ce ratio of 16/1 possessed the best catalytic benzene oxidation activity due to larger quantities of surface hydroxyl groups and surface oxygenated species. The mesostructured Co3O4-CeO2 material thus shows great potential as a promising eco-environmental catalyst for benzene effective elimination.
文摘CeO2-Co3O4 catalysts for low-temperature CO oxidation were prepared by a co-precipitation method. In combination with the characterization methods of N2 adsorption/desorption, XRD, temperature-programmed reduction (TPR), and FT-IR, the influence of the cerium content on the catalytic performance of CeO2-Co3O4 was investigated. The results indicate that the prepared CeO2-Co3O4 catalysts exhibit a better activity than that of pure CeO2 or pure Co3O4. The catalyst with the Ce/Co atomic ratio 1 : 16 exhibits the best activity, which converts 77% of CO at room temperature and completely oxidizes CO at 45 ℃.
基金supported by the National Natural Science Foundation of China(51478285,21407111)Natural Science Foundation of Jiangsu Province(BK20140280,BK20151198)+2 种基金Collegiate Natural Science Fund of Jiangsu Province(14KJA430004,16KJA430008)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Jiangsu Collaborative Innovation Center of Technology and Material for Water Treatment,Excellent Innovation Team in Science and Technology of Education Department of Jiangsu Province
文摘Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 nano-particles herein by using flower stem as biotemplate. The resulting samples were characterized by field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM), Raman spectra, X-ray diffraction spectroscopy(XRD), nitrogen adsorption and desorption, X-ray photoelectron spectrogram(XPS), and electrochemical test. The 3D graphene acted as an excellent carrier together with Co_3O_4-CeO_2 nano-particles, boosting the specific capacitance of composite(221 F/g), which exceeded the theoretical value limit. This facile biotemplate method of research provided an eco-friendly and cut-price route to obtain high-quality graphene and Co_3O_4-CeO_2nano-composites owing to the unique porous structure derived from original template(flower stem). The finding presented a simple strategy for fabrication of novel energy storage devices.