The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol...The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, infrared spectroscopy（IR） and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.展开更多
A novel strategy, which is better-suited for preparing materials with a very microscopic structure, is described and the whisker-like composite of Co(OH) 2/HY was prepared by using this strategy. In addition, the mech...A novel strategy, which is better-suited for preparing materials with a very microscopic structure, is described and the whisker-like composite of Co(OH) 2/HY was prepared by using this strategy. In addition, the mechanism by which the growth proceeds is not very rigorously worked out. Due to the high dispersed capability of HY towards to Co(OH) 2 resulting in loose whisker-like microstructure of Co(OH) 2, small channels become available for the diffusion of OH - electrolyte ions through all Co(OH) 2 thin layer. Consequentially, the prepared composite shows a very high specific capacitance (483 F/g) and utilization (93%) of effective electroactive composition of composite.展开更多
Porous anodic aluminum oxide（AAO） templates, obtained by anodization of aluminum sheets at relatively high voltages, were used for fabricating branched platinum nanowires which copy the three-dimensional branching s...Porous anodic aluminum oxide（AAO） templates, obtained by anodization of aluminum sheets at relatively high voltages, were used for fabricating branched platinum nanowires which copy the three-dimensional branching structure of the nanochannels in the template. The formation of these branched nanochannels is the characteristic of AAO templates grown at 60 V in 0.15 mol/L H2C2O4 solution. When AAO templates are grown at 40 V or lower, straight channels and platinum nanowires are obtained. Platinum nanowires array was alter-current（AC）-electrodeposited in AAO at a lower frequency（20 Hz） and increasing voltage（5-15 V）. Compared with traditional AC electrodeposition condition, the deposition rate of platinum nanowires under this condition is slower and more controllable. Therefore, the platinum nanowires can perfectly copy the structure of the template. The as-obtained Al/AAO/Pt composite and branched platinum nanowires were characterized by X-ray diffraction（XRD） and transmission electron microscope（TEM）, respectively.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
The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscop...The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscopy (RA-FTIR). All these azobenzene SAMs have highly-organized and closely-parked structures, with the molecule tilting away gradually from surface normal direction with the increase of end group alkyl length.展开更多
文摘The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, infrared spectroscopy（IR） and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.
文摘A novel strategy, which is better-suited for preparing materials with a very microscopic structure, is described and the whisker-like composite of Co(OH) 2/HY was prepared by using this strategy. In addition, the mechanism by which the growth proceeds is not very rigorously worked out. Due to the high dispersed capability of HY towards to Co(OH) 2 resulting in loose whisker-like microstructure of Co(OH) 2, small channels become available for the diffusion of OH - electrolyte ions through all Co(OH) 2 thin layer. Consequentially, the prepared composite shows a very high specific capacitance (483 F/g) and utilization (93%) of effective electroactive composition of composite.
文摘Porous anodic aluminum oxide（AAO） templates, obtained by anodization of aluminum sheets at relatively high voltages, were used for fabricating branched platinum nanowires which copy the three-dimensional branching structure of the nanochannels in the template. The formation of these branched nanochannels is the characteristic of AAO templates grown at 60 V in 0.15 mol/L H2C2O4 solution. When AAO templates are grown at 40 V or lower, straight channels and platinum nanowires are obtained. Platinum nanowires array was alter-current（AC）-electrodeposited in AAO at a lower frequency（20 Hz） and increasing voltage（5-15 V）. Compared with traditional AC electrodeposition condition, the deposition rate of platinum nanowires under this condition is slower and more controllable. Therefore, the platinum nanowires can perfectly copy the structure of the template. The as-obtained Al/AAO/Pt composite and branched platinum nanowires were characterized by X-ray diffraction（XRD） and transmission electron microscope（TEM）, respectively.
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.
文摘The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscopy (RA-FTIR). All these azobenzene SAMs have highly-organized and closely-parked structures, with the molecule tilting away gradually from surface normal direction with the increase of end group alkyl length.
