We have produced thin film samples of cubic ZnS by the chemical bath method. These samples were synthesized using zinc chloride, thiourea, sodium citrate and ammonia solutions at varied deposition time from 24h to 96h. X-ray diffraction (XRD), transmittance and photoluminescence (PL) analyses provided the physical characteristics of cubic ZnS films with crystal plane orientations (2 0 0) and (2 2 2), lattice parameters of 5.648 Å and an atomic plane distance d=1.412 Å. The grain size calculed are 16.53 nm and 17.12 nm. PL revealed deep defects in the gap with peaks in the visible, with prominent emissions at 430 nm (blue) and 510 nm (green). The measured transmittance of the films is 88.6%.

The development of membranes for nanofiltration with ionic transport properties that combine ionic permeability and selectivity is essential for improving the performance of water desalination or blue energy generation systems [1]. Besides, lab-on-chips using one or a few nano-channels combining ionic and electronic transport could open up a whole field of fundamental explorations in bio-iono-electronics and its potential applications: single-molecule detection, artificial synapses/neurons, .... etc [2]. Within this general framework, our aim is to study the ion transport properties of a bioinspired artificial nano-channel consisting of a single-walled carbon nanotube (SWCNT) inside which a biological ion channel (BIC) is confined. The first phase of this project consists of verifying whether or not it is possible to confine such a channel in a SWCNT. The BIC being studied is gramicidin. It is a small, well-characterised protein having a helicoidal structure when inserted into the cytoplasmic membrane [3]. Its outer ring is particularly hydrophobic and hence should facilitate its insertion into a SWCNT. The SWCNTs used are purified EC-15 eDIPS whose average diameter, i.e. ~2.1-2.2 nm, is expected to be large enough to accommodate the protein in its helicoidal form. The results presented here show that gramicidin strongly interacts with SWCNTs and gets inserted. This outcome is obtained using a range of technics: XRD, Raman, XPS, TEM and Water Sorption Isotherms. Particular emphasis will be made on the use of Water Sorption Isotherms as a powerful tool for characterising confinement in SWCNT.

Dyes are encapsulated into single-walled carbon nanotubes to elaborate hy-brid nano-systems with tunable optical and electronic properties. The physical interaction be-tween the confined molecules and the host nanotube is a key factor1,2.From Raman spectroscopy and G-band shift measurements, a significant charge transfer from the confined dye to the nanotube is evidenced. A photo-activated electron transfer is also inferred for small diameter (~9 Å) semiconducting and metallic tubes.3 The key parameters that govern the charge transfer are the nanotube diameter and the electron donor or acceptor character of the molecules. Furthermore, photoluminescence intensities of nanotubes are either significantly en-hanced or quenched depending on the electron donor or acceptor character of the molecules.5The resonance Raman intensities of the confined molecules are strongly affected by applying an external pressure.4 DFT Calculations clearly allow to account for this effect.Therefore, molecule confinement into nanotubes is an efficient strategy for the engineering of new opto-electronic devices.

Here, we report the development of a homemade experimental setup to perform under vacuum an in situ study of the physical properties of bundles of single-walled carbon nanotubes intercalated with rubidium ions using electrical conductivity, X-ray absorption and Raman measurements. This set-up was successfully used at the SAMBA beamline at the Soleil synchrotron. The electrical resistance displays an important drop with the stoichiometry (intercalation time). The Raman radial breathing modes and the G-band of the nanotubes clearly indicate an important electron transfer. The G-band behaviour features a transition from semiconducting to metallic nanotubes, confirmed by the electrical resistance measurements as a function of the temperature after rubidium intercalation. This set-up can be used for the study of any type of extremely air sensitive materials.

Photoluminescence of single-walled carbon nanotubes is monitored at the individual scale by molecule encapsulation into their hollow core. Depending on the electronic character (electron donor or acceptor) of the confined molecule, enhancement or quenching of the photoluminescence intensity is demonstrated. This behavior is assigned to a charge transfer, evidenced by the shift of the Raman G-band, and a correlated Fermi level shift shown by photoemission experiments. Our experimental results are supported by DFT calculations. A consistent picture of the physical interactions taking place in the hybrid systems and their effects on the optical and electronic properties is given. Our results indicate that the electron affinity or ionization potential of the encapsulated molecules and the diameter of the nanotube are relevant parameters to tune the light emission properties of the hybrid systems at the nanoscale.

Filling carbon nanotubes with molecules is a route for the development of electronically modified one-dimensional hybrid structures for which the interplay between the electronic structure of molecules and nanotubes is a key factor. Tuning these energy levels with external parameters is an interesting strategy for the engineering of new devices and materials. Here we show that the hybrid system composed by quaterthiophene (4T) molecules confined in single-walled carbon nanotubes, presents a piezo-Raman-resonance of the molecule vibrational pattern. This behavior manifests as a rapid pressure induced enhancement of the 4T Raman mode intensities compared to the tubes G-band Raman modes. Density functional theory calculations allow to explain the spectral behaviour through the pressure-enhanced quaterthiophene resonance evolution. By increasing pressure, the tube cross-section deformation leads to a reduction of the intermolecular distance, to the splitting of the molecular levels and then to an increase of resonance channels. Calculations and experiments converge to the 4T piezo-resonance scenario associated with the pressure-induced nanotube radial collapse observed at about 0.8 GPa. Our findings offer possibilities for the development of pressure transducers based on molecule-filled carbon nanotubes.

Dye confinement into carbon nanotube significantly affects the electronic charge density distribution of the final hybrid system. Using the electron-phonon coupling sensitivity of the Raman G-band, we quantify experimentally how charge transfer from thiophene oligomers to single walled carbon nanotube is modulated by the diameter of the nano-container and its metallic or semiconducting character. This charge transfer is shown to restore the electron-phonon coupling into defected metallic nanotubes. For sub-nanometer diameter tube, an electron transfer optically activated is observed when the excitation energy matches the HOMO-LUMO transition of the confined oligothiophene. This electron doping accounts for an important enhancement of the photoluminescence intensity up to a factor of nearly six for optimal confinement configuration. This electron transfer shifts the Fermi level, acting on the photoluminescence efficiency. Therefore, thiophene oligomer encapsulation allows modulating the electronic structure and then the optical properties of the hybrid system.