ZnO nanoparticles with an average size of 125 nm were prepared via homogeneous precipitation method and were characterized by SEM.The products were surface-modified by the surfactant SDS.Surface-modified nano particle...ZnO nanoparticles with an average size of 125 nm were prepared via homogeneous precipitation method and were characterized by SEM.The products were surface-modified by the surfactant SDS.Surface-modified nano particles were added at a mass ratio of 1.0%,2.0%,3.0%,and 4.0%,respectively,in base oil and their friction and wear behaviors were evaluated on a MRS-10D type four-ball wear tester.After four-ball wear tests,the morphology of the rubbing surfaces was evaluated with metallographic microscope.It was revealed that the modified nano ZnO had excellent behavior for improving anti-wear property and friction coefficient,which could greatly reduce the friction of machine parts.展开更多
ZnO nano-particles were synthesized via an ammonical ammonium carbonate solution by precipitation method in presence of some additives such as urea, oleic and stearic acid. The morphology and crystallinity of the obta...ZnO nano-particles were synthesized via an ammonical ammonium carbonate solution by precipitation method in presence of some additives such as urea, oleic and stearic acid. The morphology and crystallinity of the obtained zinc oxide particles depend critically on the type of additive which was used. Additives also affected the crystal orientation of precipitate nano-particles. SEM, XRD, BET and UV-visible were used to characterize morphology, microstructure, specific surface area and optical properties of the products.Photo-catalysis properties of the as-prepared ZnO powders were evaluated by degradation of methyl red(acid red) in aqueous solution exposed to UV-light. Results suggested a close relationship among the morphology,size and surface area on photo-catalysis and optical properties of the particles. The widest Egvalue(3.56 e V),highest degradation and decolorization efficiency(99%) were obtained from a sample with the smallest grain size(largest surface area) which were used urea as an additive.展开更多
Ni（OH）2 with a high specific surface area was synthesized by a facile fast precipitation method.Porous nano-NiO was obtained by calcining Ni（OH）2 at 300 ℃.The NiO sample possesses a fine porous distribution at ar...Ni（OH）2 with a high specific surface area was synthesized by a facile fast precipitation method.Porous nano-NiO was obtained by calcining Ni（OH）2 at 300 ℃.The NiO sample possesses a fine porous distribution at around 3-10 nm.The BET specific surface area and pore volume of this sample are 218.1 m2/g and 0.31 cm3/g,respectively.The electrochemical characteristics of the samples were studied by cyclic voltammetry and constant current charge/discharge.The specific capacitance of the NiO sample is about 255 F/g in the 2.0 mol/L KOH solution.The sample also has a fine electrochemical stability.展开更多
基金supported by Liaoning Provincial Office of Education for Innovation Team (Project number:2006T001)Liaoning Province of Key Laboratory Project (Project number:2008403001)
文摘ZnO nanoparticles with an average size of 125 nm were prepared via homogeneous precipitation method and were characterized by SEM.The products were surface-modified by the surfactant SDS.Surface-modified nano particles were added at a mass ratio of 1.0%,2.0%,3.0%,and 4.0%,respectively,in base oil and their friction and wear behaviors were evaluated on a MRS-10D type four-ball wear tester.After four-ball wear tests,the morphology of the rubbing surfaces was evaluated with metallographic microscope.It was revealed that the modified nano ZnO had excellent behavior for improving anti-wear property and friction coefficient,which could greatly reduce the friction of machine parts.
文摘ZnO nano-particles were synthesized via an ammonical ammonium carbonate solution by precipitation method in presence of some additives such as urea, oleic and stearic acid. The morphology and crystallinity of the obtained zinc oxide particles depend critically on the type of additive which was used. Additives also affected the crystal orientation of precipitate nano-particles. SEM, XRD, BET and UV-visible were used to characterize morphology, microstructure, specific surface area and optical properties of the products.Photo-catalysis properties of the as-prepared ZnO powders were evaluated by degradation of methyl red(acid red) in aqueous solution exposed to UV-light. Results suggested a close relationship among the morphology,size and surface area on photo-catalysis and optical properties of the particles. The widest Egvalue(3.56 e V),highest degradation and decolorization efficiency(99%) were obtained from a sample with the smallest grain size(largest surface area) which were used urea as an additive.
文摘Ni（OH）2 with a high specific surface area was synthesized by a facile fast precipitation method.Porous nano-NiO was obtained by calcining Ni（OH）2 at 300 ℃.The NiO sample possesses a fine porous distribution at around 3-10 nm.The BET specific surface area and pore volume of this sample are 218.1 m2/g and 0.31 cm3/g,respectively.The electrochemical characteristics of the samples were studied by cyclic voltammetry and constant current charge/discharge.The specific capacitance of the NiO sample is about 255 F/g in the 2.0 mol/L KOH solution.The sample also has a fine electrochemical stability.
