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The work presented here describes new UV-crosslinkable thin layer polymeric materials for the encapsulation of ZnO nanowires (NWs) in multi-NWs pressure based fingerprint sensors. Such innovative sensor is a novel technology for fingerprint capture developed within the PiezoMAT FP7 European project. The sensing principle is based on the piezoelectric property of ZnO NWs, on which a potential difference is generated when they undergo compression and/or bending forces. Since the pressure induced by the finger cannot be directly applied on the NWs, the deformation is applied through a polymeric material that aims at transferring forces from the finger onto the array of NWs without altering their integrity. Besides, since it is dedicated to be in direct contact with human finger or oil pollutants, the encapsulation layer must also exhibit chemical inertness, as well as hydrophobicity and oleophobicity.

This paper reports the optimization and the characterization of a 4 cm diameter water flow energy harvester inserted in pipes. In this work, a test-bench has been implemented to measure the harvester’s electrical output powers, rotation frequencies and pressure losses. Furthermore, long-term tests have been carried out in a district heating and cooling system (DHCS) in order to validate its operation in a real environment. Output powers up to 490mW @ 9 m3.h−1 are reported with a mean output power of 5mW in real conditions (Montpellier’s DHCS in France). The pressure losses induced by the turbine and the energy extraction remains lower than 50 mbars which is among the lowest in the state of the art.

The continuous contamination of the cathode with chromium released from metallic interconnects speeds up the degradation of the performance of the cell. For this reason Solid Oxide Fuel Cell (SOFC) interconnects are coated with a dense protective layer. This layer plays the role of a diffusion barrier for the chromium evaporation at operating conditions. The deposition of a dense, gas tight and stable MnCo2O4 spinel layer on ferritic alloy using the atmospheric plasma spraying (APS) process is studied. The first experimental results show that the plasma spray process combined with an appropriate post thermal-treatment is suitable to form a dense spinel protective layer.

This paper reports on the performances and the optimization of a 40 mm diameter water flow energy harvester based on an axial turbine (horizontal axis propeller) coupled to a customized permanent magnet generator. To the best of our knowledge, this work is one of the first comprehensive studies in the low dimensional and flow velocities ranges. The parameters of the propeller have been empirically optimized (\(\lambda_D\)=1, B=4 blades) by the means of experiments in a test-bench pipe at various flow rates from 1 to 9 m3 h−1. The best propeller design has been selected for its performances in terms of electrical power and pressure drop. A customized permanent magnet converter with ferromagnetic elements has been modeled, optimized with finite elements simulations and fabricated. This has enabled to increase the electrical power by 2.7 @ 1.5 m3 h−1 (3.2 mW) and up to 14.1 @ 9 m3 h−1 (490 mW) compared to a simple magnet-air coil converter. The figure of merit of our water flow harvester, which takes the electrical power and the pressure drops in the pipe into account, is greater than previously reported water flow energy harvesters, and corresponds to an overall mechanical-to-electrical conversion efficiency of 5.15%.