0000000001257922
AUTHOR
Amélie Wannebroucq
Electrochemical and Spectroelectrochemical Behavior of a Tetracyanotriphenodioxazine in Solution and Thin-Films
International audience; We report the electrochemical behavior of a tetracyano triphenodioxazine bearing two triisopropylsilylethynyl moieties (TiPS‐TPDO‐tetraCN) during its reduction studied either in solution or after vacuum evaporation deposition on indium tin oxide (ITO) support. While in dichloromethane, it typically proceeds in two successive monoelectronic reactions, in acetonitrile, the mechanism appears more complex. Fine analysis of the spectroelectrochemical results combined with simulation of the voltammograms with various amount of water suggest the involvement of water and of a restructured dianion in the electrochemical process. In the solid‐state, the formation of the diprot…
A tungsten oxide–lutetium bisphthalocyanine n–p–n heterojunction: from nanomaterials to a new transducer for chemo-sensing
We report on a new hybrid heterojunction gas-sensitive device by combining a molecular material with a metal oxide. WO3 was synthesised via an aerosol-assisted chemical vapour deposition technique from a tungsten hexacarbonyl precursor. Onto an inorganic film, LuPc2 was vacuum evaporated. The morphology of the WO3–LuPc2 hybrid films is dominated by the morphological features of the tungsten oxide film, as shown by scanning electron microscopy and atomic force microscopy. Raman spectroscopy of the device confirms the presence of both materials. The non-linear I–V characteristics demonstrate the existence of an energy barrier at the interface between the inorganic and molecular materials. The…
New n-type molecular semiconductor–doped insulator (MSDI) heterojunctions combining a triphenodioxazine (TPDO) and the lutetium bisphthalocyanine (LuPc2) for ammonia sensing
International audience; Molecular semiconductor–doped insulator (MSDI) heterojunctions were designed using a new family of sublayers, namely triphenodioxazines (TPDO). The device obtained by combining the tetracyano triphenodioxazine bearing two triisopropylsilylethynyl moieties as a sublayer with the lutetium bisphthalocyanine (LuPc2) as a top layer showed a nonlinear current–voltage characteristic independent of the sign of the polarization, which is the signature of MSDI heterojunctions. Thus, a TPDO was used in a chemical sensor for the first time. Despite LuPc2 being the only material exposed to the atmosphere, the positive response of the device under ammonia revealed the key role pla…
Bias and humidity effects on the ammonia sensing of perylene derivative/lutetium bisphthalocyanine MSDI heterojunctions
International audience; In this paper, we prepared and studied sensors based on Molecular Semiconductor-Doped Insulator (MSDI) heterojunctions. These original devices are built with two stacked layers of molecular materials and exhibit very specific electrical and sensing properties. We studied the properties of a MSDI composed of the perylenetetracarboxylic dianhydride, PTCDA, or the fluorinated perylenebisimine derivative, C4F7-PTCDI, as n-type molecular material sublayers, and LuPc2 as a p-type semiconductor top layer. Their response to ammonia was compared to that of a resistor formed of only the top layer of the MSDI (LuPc2). Ammonia increases the current in the MSDIs whereas it causes…
Quel emploi pour les jeunes chimistes ?
L'emploi scientifique recouvre l'en-semble des personnes travaillant directe-ment sur les projets de recherche et déve-loppement, qu'ils soient doctorants, chercheurs ou enseignants-chercheurs, personnels de soutien à la recherche du secteur public (hors défense) ou du sec-teur privé. Nous nous intéressons ici à l'état de l'emploi scientifique en France, en particulier dans la filière « chimie », en dissociant le secteur public-univer-sités et établissements d'enseignement supérieur, établissements publics à caractère scientifique et technologique (EPST), établissements publics à carac-tère industriel et commercial (EPIC), centres hospitaliers universitaires (CHU), institutions sans but luc…
On the interest of ambipolar materials for gas sensing
International audience; Based on the electrochemical properties of a series of metallophthalocyanines this article shows that the phthalocyanine bearing four alkoxy groups and twelve fluorine atoms behaves approximately as those with eight fluorine atoms. This indicates that the electron-donating effect of one alkoxy group balances the electro-withdrawing effect of one fluorine atom. We engaged three metallophthalocyanines, namely the octafluoro copper phthalocyanine, Cu(F8Pc), an octaester metallophthalocyanine and a phthalocyanine bearing four alkoxy groups and twelve fluorine atoms, Zn(T4F12Pc), in building original conductometric transducers that are Molecular Semiconductor – Doped Insu…
Synthesis of molecular materials and heterojunctions, on the interest of ambipolar materials in conductometric gas sensors
The molecular semiconductors have enabled the production of electronic devices such as field effect transistors, diodes and other heterojunctions. The ambipolar materials, capable of carrying both positive charges and negative, result in devices with special properties. The purpose of this thesis is to synthesize new ambipolar materials develop original electronic devices, especially for applications in the field of gas sensors. We are interested in molecules capable to lead to thin films with low temperature techniques known as solution processing, particularly metallo-phthalocyanines.
Molecular Semiconductors — Doped Insulator (MSDI) heterojunctions as new conductometric devices for chemosensing in wet atmosphere.
Most of the gas sensors are based on resistors with inorganic materials and more rarely on other conductometric devices (diodes or transistors). Conductometric sensors have also been designed with molecular materials. Thus, in 2009, Molecular Semiconductor — Doped-insulator (MSDI) heterojunctions were built around a heterojunction between a molecular semiconductor (MS) and a doped-insulator (DI). The MS must be more conductive than the sublayer to take advantage of the heterojunction. The MS is generally of p-type and DI can be of p-type (p-MSDI) or n-type (n-MSDI) material. The energy barrier at the interface depends on the difference in the charge carrier density in the two layers, leadin…
CCDC 1497477: Experimental Crystal Structure Determination
Related Article: Amélie Wannebroucq, Rita Meunier-Prest, Jean-Claude Chambron, Claire-Hélène Brachais, Jean-Moïse Suisse, Marcel Bouvet|2017|RSC Advances|7|41272|doi:10.1039/C7RA05325H