The functionalization of single-walled carbon nanotubes (SWCNTs) with luminescent sp3 defects has greatly improved their performance in applications such as quantum light sources and bioimaging. Here, we report the covalent functionalization of purified semiconducting SWCNTs with stable organic radicals (perchlorotriphenylmethyl, PTM) carrying a net spin.
This model system allows us to use the near-infrared photoluminescence arising from the defect-localized exciton as a highly sensitive probe for the short-range interaction between the PTM radical and the SWCNT. Our results point toward an increased triplet exciton population due to radical-enhanced intersystem crossing, which could provide access to the elusive triplet manifold in SWCNTs. Furthermore, this simple synthetic route to spin-labeled defects could enable magnetic resonance studies complementary to in vivo fluorescence imaging with functionalized SWCNTs and facilitate the scalable fabrication of spintronic devices with magnetically switchable charge transport.
Tuneable and low cost molecular electronics
Interaction of Luminescent Defects in Carbon Nanotubes with Covalently Attached Stable Organic Radicals
Felix J. Berger, J. Alejandro de SousaJ. Alejandro de Sousa, Shen Zhao, Nicolas F. Zorn, Abdurrahman Ali El Yumin, Aleix Quintana García, Simon Settele, Alexander Högele, Núria Crivillers, and Jana Zaumseil*
While oxidation of d8 anionic gold bis(dithiolene) complexes most often affords the corresponding neutral radical single-component conductor, an original gold bis(diselenolene) complex isolated as a Ph4P+ salt affords upon electrocrystallization a mixed-valence 1 : 2 salt, [Ph4P][Au(Me-thiazds)2]2 (Me-thiazds: 2-methyl-1,3-thiazoline-2-thione-4,5-diselenolate).
When we speak of nanometric water films on surfaces we are speaking about a truly ubiquitous phenomenon in nature. All surfaces exposed to ambient conditions are covered by a thin film of water that affects or mediates surface chemistry, general physical-chemical processes on surfaces, and even solid–solid interactions.
Electrocrystallization of tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) (1) as pure (S,S,S,S) and (R,R,R,R) enantiomers in the presence of (n-Bu4N)2(Mo6O19) and chloroform or bromoform afforded a series of four isostructural enantiopure radical cation salts [(S/R)-1]9(Mo6O19)5·(CHX3)2 (X = Cl, Br) crystallizing in the trigonal non-centrosymmetric space group R32.
The dramatic consequences that the orientation adopted by the molecular dipoles, in diverse arrays of chloroaluminum phthalocyanine (ClAlPc) on Au(111), have on the ulterior adsorption and growth of C60 are explored by means of an all scanning probe microscopy approach. The unidirectional downwards organization of the molecular dipoles at the first layer reduces charge transfer from the metal to C60. Imbalance between attractive and repulsive interactions of the fullerenes are crucial for their ordered supramolecular aggregation.
To date, crystallization studies conducted in space laboratories, which are prohibitively costly and unsuitable to most research laboratories, have shown the valuable effects of microgravity during crystal growth and morphogenesis. Herein, an easy and highly efficient method is shown to achieve space-like experimentation conditions on Earth employing custom-made microfluidic devices to fabricate 2D porous crystalline molecular frameworks.