To improve the performance of battery cathode materials that consist of carbonaceous organic material, carbon coatings on lithium iron phosphate （LiFePO4/C） materials were synthesized by different carbon sources. Li...To improve the performance of battery cathode materials that consist of carbonaceous organic material, carbon coatings on lithium iron phosphate （LiFePO4/C） materials were synthesized by different carbon sources. LiFePO4/C was synthesized by a combination method of sol-gel and gas-phase diffused permeation. LiFeO4/C materials were prepared by coating different carbon con- tents. High-performance composite materials were pre- pared by combining carbon with element doped by two modified methods. The elements of Fe and C came from Fe3＋ and sucrose, glucose, citric acid. Thermogravimetry- differential thermal analysis （TG-DTA）, X-ray diffrac- tometer （XRD）, scanning electron microscope （SEM）, cycle voltammetry （CV）, and charge-discharge test were used to characterize and test the surface morphology, structure, and electrochemical performance. The results show that LiFePO4/C synthesized with sucrose has higher specific discharge capacity than the other materials. The specific discharge capacity of this material is 84.27 mAh.g-1. The capacity retention could attain 94 % of the initial discharge capacity after 30 cycles, showing good electrochemical performance.展开更多
Ternary europium complex with dibenzoylmethane(DBM)and 1,10phenanthroline(phen)was insitu synthesized in thin SiO2/polyvinyl butyral(PVB)hybrid films by a twostep solgel process and characterized by means of fluoresce...Ternary europium complex with dibenzoylmethane(DBM)and 1,10phenanthroline(phen)was insitu synthesized in thin SiO2/polyvinyl butyral(PVB)hybrid films by a twostep solgel process and characterized by means of fluorescence spectroscopy.The luminescence spectra,fluorescence lifetimes and photostability were all investigated.The results showed that the hybrid films exhibited the characteristic emission bands of the central rare earth Eu3+.In addition,Eu3+presented longer fluorescence lifetime than in an ethanol solution and the complex had a higher photostability in the hybrid film than in the PVB film containing the corresponding pure complex.展开更多
In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained a...In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained an amorphous state up to 500.The activation energy was calculated to be 252 kJ/mol according to the modified Kissinger equation.展开更多
A new sub-micron photolithography tool has been realized by utilizing the interference of surface plasmon waves(SPWs) on the near surface of a silver(Ag)-clad ultraviolet(UV) planar waveguide.A laser beam with a wavel...A new sub-micron photolithography tool has been realized by utilizing the interference of surface plasmon waves(SPWs) on the near surface of a silver(Ag)-clad ultraviolet(UV) planar waveguide.A laser beam with a wavelength of 325 nm was incident into the waveguide core,and suffered a series of total internal reflections on the interfaces between the waveguide core and the cladding layers.The incident light and the reflected light induced two beams of SPWs traveling in contrary directions,which interfered with each other and formed a standing wave as a sub-micron photolithography tool.A near-field scanning optical microscope(NSOM) was employed to measure the intensity distribution of the stationary wave field of the near surface of the Ag layer of the waveguide,anastomosed with theoretical values acquired by use of finite difference time domain(FDTD) simulations.And with this sub-micron photolithography tool a SMG with a period of 79.3 nm,in good agreement with the theoretical value of 80.1 nm,was inscribed on the surface of a self-processing hybrid SiO2/ZrO2 solgel film for the first time.展开更多
基金financially supported by the National Natural Science Foundation of China (No.51274143)
文摘To improve the performance of battery cathode materials that consist of carbonaceous organic material, carbon coatings on lithium iron phosphate （LiFePO4/C） materials were synthesized by different carbon sources. LiFePO4/C was synthesized by a combination method of sol-gel and gas-phase diffused permeation. LiFeO4/C materials were prepared by coating different carbon con- tents. High-performance composite materials were pre- pared by combining carbon with element doped by two modified methods. The elements of Fe and C came from Fe3＋ and sucrose, glucose, citric acid. Thermogravimetry- differential thermal analysis （TG-DTA）, X-ray diffrac- tometer （XRD）, scanning electron microscope （SEM）, cycle voltammetry （CV）, and charge-discharge test were used to characterize and test the surface morphology, structure, and electrochemical performance. The results show that LiFePO4/C synthesized with sucrose has higher specific discharge capacity than the other materials. The specific discharge capacity of this material is 84.27 mAh.g-1. The capacity retention could attain 94 % of the initial discharge capacity after 30 cycles, showing good electrochemical performance.
文摘Ternary europium complex with dibenzoylmethane(DBM)and 1,10phenanthroline(phen)was insitu synthesized in thin SiO2/polyvinyl butyral(PVB)hybrid films by a twostep solgel process and characterized by means of fluorescence spectroscopy.The luminescence spectra,fluorescence lifetimes and photostability were all investigated.The results showed that the hybrid films exhibited the characteristic emission bands of the central rare earth Eu3+.In addition,Eu3+presented longer fluorescence lifetime than in an ethanol solution and the complex had a higher photostability in the hybrid film than in the PVB film containing the corresponding pure complex.
文摘In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained an amorphous state up to 500.The activation energy was calculated to be 252 kJ/mol according to the modified Kissinger equation.
基金supported by the Natural Science Foundation of Guangdong Province, China (Grant Nos.8251063101000007, 10151063101000009,and 9451063101002082)the Scientific and Technological Plan of Guangdong Province (Grant Nos.2008B010200004, 2010B010600030, and 2009B011100003)the National Natural Science Foundation of China (Grant Nos.61078046 and 60977048)
文摘A new sub-micron photolithography tool has been realized by utilizing the interference of surface plasmon waves(SPWs) on the near surface of a silver(Ag)-clad ultraviolet(UV) planar waveguide.A laser beam with a wavelength of 325 nm was incident into the waveguide core,and suffered a series of total internal reflections on the interfaces between the waveguide core and the cladding layers.The incident light and the reflected light induced two beams of SPWs traveling in contrary directions,which interfered with each other and formed a standing wave as a sub-micron photolithography tool.A near-field scanning optical microscope(NSOM) was employed to measure the intensity distribution of the stationary wave field of the near surface of the Ag layer of the waveguide,anastomosed with theoretical values acquired by use of finite difference time domain(FDTD) simulations.And with this sub-micron photolithography tool a SMG with a period of 79.3 nm,in good agreement with the theoretical value of 80.1 nm,was inscribed on the surface of a self-processing hybrid SiO2/ZrO2 solgel film for the first time.
