We have demonstrated here the dissociation behavior of carboxylic groups at the open end of Single\|Walled Carbon Nanotubes(SWNTs) by tip chemistry. SWNTs were cut into short pipes by acid oxidation and thus carboxyli...We have demonstrated here the dissociation behavior of carboxylic groups at the open end of Single\|Walled Carbon Nanotubes(SWNTs) by tip chemistry. SWNTs were cut into short pipes by acid oxidation and thus carboxylic groups were produced at the end of the tubes. The SWNTs can be immobilized onto AFM tips by surface condensation between amino\|terminated self\|assembled monolayers(SAMs) on AFM tips and carboxylic groups at the end of SWNTs. The p\%K\%\-\{1/2\} value of the SWNTs was then obtained from the force titration measurements of the SWNTs tips \%vs\%. hydroxyl\|terminated SAMs. The results showed a different force titration behaviour and variable p\%K\%\-\{1/2\} values among different SWNTs tips, indicating the variations in the chemistry from tube to tube.展开更多
A polydiacetylene nanocrystalline film has been fabricated using surface evaporationmethod and observed by using Aurora 2000, TopoMetrix scanning near-field optical microscope(SNOM) system. The SNOM images of this fil...A polydiacetylene nanocrystalline film has been fabricated using surface evaporationmethod and observed by using Aurora 2000, TopoMetrix scanning near-field optical microscope(SNOM) system. The SNOM images of this film together with the standard testing Al sampleindicate that the resolution of the system is better than 80 nm 1/6 of the incident wavelength,488 nm. The possibility of SNOM data storage using thus fabricated film is also demonstrated.展开更多
文摘We have demonstrated here the dissociation behavior of carboxylic groups at the open end of Single\|Walled Carbon Nanotubes(SWNTs) by tip chemistry. SWNTs were cut into short pipes by acid oxidation and thus carboxylic groups were produced at the end of the tubes. The SWNTs can be immobilized onto AFM tips by surface condensation between amino\|terminated self\|assembled monolayers(SAMs) on AFM tips and carboxylic groups at the end of SWNTs. The p\%K\%\-\{1/2\} value of the SWNTs was then obtained from the force titration measurements of the SWNTs tips \%vs\%. hydroxyl\|terminated SAMs. The results showed a different force titration behaviour and variable p\%K\%\-\{1/2\} values among different SWNTs tips, indicating the variations in the chemistry from tube to tube.
文摘A polydiacetylene nanocrystalline film has been fabricated using surface evaporationmethod and observed by using Aurora 2000, TopoMetrix scanning near-field optical microscope(SNOM) system. The SNOM images of this film together with the standard testing Al sampleindicate that the resolution of the system is better than 80 nm 1/6 of the incident wavelength,488 nm. The possibility of SNOM data storage using thus fabricated film is also demonstrated.