Single wail carbon nanotubes （SWNTs） are known for their exceptional electronic properties. However, most of the synthesis methods lead to the production of a mixture of carbon nanotubes having different chiralities...Single wail carbon nanotubes （SWNTs） are known for their exceptional electronic properties. However, most of the synthesis methods lead to the production of a mixture of carbon nanotubes having different chiralities associated with metallic （m-SWNTs） and semiconducting （s-SWNTs） characteristics. For application purposes, effective methods for separating these species are highly desired. Here, we report a protocol for achieving a highly selective separation of s-SWNTs that exhibit a fundamental optical transition centered at 1,550 nm. We employ a polymer assisted sorting approach, and the influence of preparation methods on the optical and transport performances of the separated nanotubes is analyzed. As even traces of m-SWNTs can critically affect performances, we aim to produce samples that do not contain any detectable fraction of residual m-SWNTs.展开更多
As dipyranylidenes are excellent hole carriers, applications in organic solar cells or organic light emitting diode are envisaged. In the present study, we investigate the morphology of 2,2＇,6,6＇-tetraphenyl-4,4＇-d...As dipyranylidenes are excellent hole carriers, applications in organic solar cells or organic light emitting diode are envisaged. In the present study, we investigate the morphology of 2,2＇,6,6＇-tetraphenyl-4,4＇-dipyranylidene （DIPO-Ph4） deposited under vacuum on a silicon nitride （Si3N4） substrate, a paradigmatic system for the study of molecular crystal/inorganic substrate interfaces. Samples with various coating ratios and different thermal treatments were prepared. The films were characterized by atomic force microscopy and scanning transmission X-ray microscopy to gain insight into material growth. The results show a change in orientation at a molecular level depending upon the evaporation conditions. We are now able to tailor an organic layer with a specific molecular orientation and a specific electronic behavior.展开更多
文摘Single wail carbon nanotubes （SWNTs） are known for their exceptional electronic properties. However, most of the synthesis methods lead to the production of a mixture of carbon nanotubes having different chiralities associated with metallic （m-SWNTs） and semiconducting （s-SWNTs） characteristics. For application purposes, effective methods for separating these species are highly desired. Here, we report a protocol for achieving a highly selective separation of s-SWNTs that exhibit a fundamental optical transition centered at 1,550 nm. We employ a polymer assisted sorting approach, and the influence of preparation methods on the optical and transport performances of the separated nanotubes is analyzed. As even traces of m-SWNTs can critically affect performances, we aim to produce samples that do not contain any detectable fraction of residual m-SWNTs.
文摘As dipyranylidenes are excellent hole carriers, applications in organic solar cells or organic light emitting diode are envisaged. In the present study, we investigate the morphology of 2,2＇,6,6＇-tetraphenyl-4,4＇-dipyranylidene （DIPO-Ph4） deposited under vacuum on a silicon nitride （Si3N4） substrate, a paradigmatic system for the study of molecular crystal/inorganic substrate interfaces. Samples with various coating ratios and different thermal treatments were prepared. The films were characterized by atomic force microscopy and scanning transmission X-ray microscopy to gain insight into material growth. The results show a change in orientation at a molecular level depending upon the evaporation conditions. We are now able to tailor an organic layer with a specific molecular orientation and a specific electronic behavior.
