Efficient Dye-Sensitized Solar Cells Made from ZnO Nanostructure Composites

International audienceWe describe a simple and low-cost wet-chemical route for the synthesis of ZnO nanowire/nanoparticle composite electrodes. The integration of such nanocomposite photoanodes in dye-sensitized solar cells (DSSCs) leads to much better photovoltaic properties than for bare nanowire or nanoparticle ensembles with a photoconversion efficiency as high as 4.7%. Importantly, beneficial effects of thermal heat treatments are investigated in terms of ZnO nanoparticle formation and DSSC photovoltaic properties. In particular, we reveal the presence of a zinc oxoacetate intermediate phase from 120 degrees C, which drastically reduces the electron leakages at the ZnO/dye/electrolyte interface, while retaining a large specific surface area and a relatively good electron injection efficiency

Effect of Nanostructuration on the Thermal Conductivity of Thermoelectric Materials

We have investigated various kinds of nanowires (Si, Bi2Te3, SiGe) in order to evaluate the influence of the nanostructuration on their thermal conductivity. The method used is a 3ω-SThM (Scanning Thermal Microscopy) technique which enables to simultaneously measure the topography and the thermal conductivity on an assembly of NWs. We detail the procedure from the measurement itself to the nanowire thermal conductivity estimation. We show that the nanostructuration leads to a thermal conductivity reduction for the 3 materials we have studied and that Si and SiGe nanowire samples seem more promising than Bi2Te3 NWs in terms of thermoelectric applications

Bidirectional light-induced conductance switching in molecular wires containing a dimethyldihydropyrene unit

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Joule Expansion Imaging Techniques on Microlectronic Devices

We have studied the electrically induced off-plane surface displacement on two microelectronic devices using Scanning Joule Expansion Microscopy (SJEM). We present the experimental method and surface displacement results. We show that they can be successfully compared with surface displacement images obtained using an optical interferometry method. We also present thermal images using Scanning Thermal Microscopy (SThM) technique to underline that SJEM is more adapted to higher frequency measurements, which should improve the spatial resolution

Joule Expansion Imaging Techniques on Microlectronic Devices

We have studied the electrically induced off-plane surface displacement on two microelectronic devices using Scanning Joule Expansion Microscopy (SJEM). We present the experimental method and surface displacement results. We show that they can be successfully compared with surface displacement images obtained using an optical interferometry method. We also present thermal images using Scanning Thermal Microscopy (SThM) technique to underline that SJEM is more adapted to higher frequency measurements, which should improve the spatial resolution

ZnO / CdTe core shell nanowires on tin dioxide thin films for solar cells

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Ultrasensitive Extended-Gate Ion-Sensitive-Field-Effect-Transistor Developed Utilizing an Industrial UTBB FDSOI Platform

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ZnO / CdTe core shell nanowires on tin dioxide thin films for solar cells

International audienc