A successful approach to assemble Au core Pd shell （Au@Pd） nanoparticles on the surface of multi-walled carbon nanotubes functionalized by methylene blue （MB） （Au@Pd/fuv-MWCNTs） was reported. In this method, MWC...A successful approach to assemble Au core Pd shell （Au@Pd） nanoparticles on the surface of multi-walled carbon nanotubes functionalized by methylene blue （MB） （Au@Pd/fuv-MWCNTs） was reported. In this method, MWCNTs were functionalized under ultraviolet irradiation. UV-Vis analysis and high-angle annular dark-field trans- mission electron microscope （HAADF-TEM） image prove that core-shell structure of Au@Pd nanoparticles forms. TEM results indicate that Au@Pd nanoparticles （ - 5.2 nm） are well-dispersed on the surface of fuv-MWCNTs. X-ray photoelectron spectroscopy （XPS） reveals that ultraviolet irradiation can promote the interaction between Au@Pd nanoparticles and the functional groups on the surface of MWCNTs. Cyclic voltammograms （CV）, chronoampero- grams （CA）, and electrochemical impedance spectroscopy （EIS） results demonstrate that the Au@Pd/fuv-MWCNTs catalysts show excellent electrocatalytic performance for methanol oxidation in alkaline media. The catalytic activity of the Au@Pd/fuv-MWCNTs is ~ 2 times higher than that of the commercial Pd/C catalysts. This is mostly attributed to that ultraviolet irradiation can make the moieties of MB provide a uniform surface with active and anchoring sites, and improves the functional effect of MB on the surface of MWCNTs. Especially, ultraviolet irradiation modifies electronic structure of Pd and is beneficial for the enhance- ment of catalytic activity.展开更多
A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owi...A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owing to the unique three-dimensional network of c-MnOOH embedded in the porous structure of MWCNTs,the c-MnOOH/MWCNTs composite could have an advantage of high electrocatalytic activities over those of two other kinds of cathode materials(MWCNTs and c-MnOOH/MWCNTs mixture).The results of chargedischarge tests showed that the c-MnOOH/MWCNTs composite as a cathode material of lithium-air batteries could effectively enhance the catalytic activity for the oxygen evolution reduction(OER)process.The lithium-air battery based on c-MnOOH/MWCNTs composite exhibits low charge potential and high discharge capacity.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51164017, 51374117, and 21363012)
文摘A successful approach to assemble Au core Pd shell （Au@Pd） nanoparticles on the surface of multi-walled carbon nanotubes functionalized by methylene blue （MB） （Au@Pd/fuv-MWCNTs） was reported. In this method, MWCNTs were functionalized under ultraviolet irradiation. UV-Vis analysis and high-angle annular dark-field trans- mission electron microscope （HAADF-TEM） image prove that core-shell structure of Au@Pd nanoparticles forms. TEM results indicate that Au@Pd nanoparticles （ - 5.2 nm） are well-dispersed on the surface of fuv-MWCNTs. X-ray photoelectron spectroscopy （XPS） reveals that ultraviolet irradiation can promote the interaction between Au@Pd nanoparticles and the functional groups on the surface of MWCNTs. Cyclic voltammograms （CV）, chronoampero- grams （CA）, and electrochemical impedance spectroscopy （EIS） results demonstrate that the Au@Pd/fuv-MWCNTs catalysts show excellent electrocatalytic performance for methanol oxidation in alkaline media. The catalytic activity of the Au@Pd/fuv-MWCNTs is ~ 2 times higher than that of the commercial Pd/C catalysts. This is mostly attributed to that ultraviolet irradiation can make the moieties of MB provide a uniform surface with active and anchoring sites, and improves the functional effect of MB on the surface of MWCNTs. Especially, ultraviolet irradiation modifies electronic structure of Pd and is beneficial for the enhance- ment of catalytic activity.
基金supported by the National High Technology Research and Development Program of China(2011AA11A255)
文摘A novel composite of monoclinic manganite/multi-walled carbon nanotubes(c-MnOOH/MWCNTs)composite as a cathode material of lithium-air batteries was successfully synthesized by a simple one-step hydrothermal method.Owing to the unique three-dimensional network of c-MnOOH embedded in the porous structure of MWCNTs,the c-MnOOH/MWCNTs composite could have an advantage of high electrocatalytic activities over those of two other kinds of cathode materials(MWCNTs and c-MnOOH/MWCNTs mixture).The results of chargedischarge tests showed that the c-MnOOH/MWCNTs composite as a cathode material of lithium-air batteries could effectively enhance the catalytic activity for the oxygen evolution reduction(OER)process.The lithium-air battery based on c-MnOOH/MWCNTs composite exhibits low charge potential and high discharge capacity.
