Organic nanotubes from two kinds of chiral molecules, R-di-2-naphthylprolinol （DNP） with an asymmetric carbon atom and R-（＋）-1,1＇-bi-2-naphthol dimethyl ether （BNDE） with the conformational asymmetry, were pre...Organic nanotubes from two kinds of chiral molecules, R-di-2-naphthylprolinol （DNP） with an asymmetric carbon atom and R-（＋）-1,1＇-bi-2-naphthol dimethyl ether （BNDE） with the conformational asymmetry, were prepared by the immersing technique using porous alumina membranes as the template. It was found that the nanotubes from DNP with an asymmetric carbon atom presented the same chirality as the solution with slight red shift of the CD signals upon the formation of the nanotubes, while no well-defined chirality could be identified for the nanotubes from BNDE with the conformational asymmetry.展开更多
Organic nanocrystals of 1,3,5-triphenyl-2-pyrazoline (TPP) with a series of sizes were synthesized by reprecipitation method. The luminescence quantum efficiency of TPP nanocrystals increases from 24.2% for the nanocr...Organic nanocrystals of 1,3,5-triphenyl-2-pyrazoline (TPP) with a series of sizes were synthesized by reprecipitation method. The luminescence quantum efficiency of TPP nanocrystals increases from 24.2% for the nanocrystals with an average size of 300 nm to 34.6% for those with an average size of 20 nm. Surface capping by polyvinyl pyrrolidone (PVP) will improve the quantum efficiency of TPP nanocrystals. The size-dependence and capping-induced variation of the luminescence quantum efficiency was elucidated in viewpoint of aggregation quenching and the equilibrium between the TPP monomers and the aggregates in TPP nanocrystals.展开更多
基金Project supported by the National Natural Science Foundation of China （Nos. 50221201, 90301010, 20373077, 20471062）, the Chinese Academy of Sciences and the National Research Fund for Fundamental Key Projects No. 973.
文摘Organic nanotubes from two kinds of chiral molecules, R-di-2-naphthylprolinol （DNP） with an asymmetric carbon atom and R-（＋）-1,1＇-bi-2-naphthol dimethyl ether （BNDE） with the conformational asymmetry, were prepared by the immersing technique using porous alumina membranes as the template. It was found that the nanotubes from DNP with an asymmetric carbon atom presented the same chirality as the solution with slight red shift of the CD signals upon the formation of the nanotubes, while no well-defined chirality could be identified for the nanotubes from BNDE with the conformational asymmetry.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina ,ChineseAcademyofSciencesandtheMajorStateBasicResearchDevelopmentProgram (No .G19990 330 )
文摘Organic nanocrystals of 1,3,5-triphenyl-2-pyrazoline (TPP) with a series of sizes were synthesized by reprecipitation method. The luminescence quantum efficiency of TPP nanocrystals increases from 24.2% for the nanocrystals with an average size of 300 nm to 34.6% for those with an average size of 20 nm. Surface capping by polyvinyl pyrrolidone (PVP) will improve the quantum efficiency of TPP nanocrystals. The size-dependence and capping-induced variation of the luminescence quantum efficiency was elucidated in viewpoint of aggregation quenching and the equilibrium between the TPP monomers and the aggregates in TPP nanocrystals.
