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The growing need for alternative sources to power Internet of Things and autonomous devices has led to many energy harvesting solutions from ambient energy sources. Use of batteries requires complementary energy source for extending the lifetime of the device. In recent times, triboelectric nanogenerators have gained significant attention in charging applications through ambient energy harvesting field due to their simplicity, efficiency and adaptability to many device configurations in nature. It is deemed to sustainably address power for autonomous smart applications in various environmental conditions. In this work, a state-of-the-art triboelectric nanogenerator based on wind actuated venturi design system is demonstrated in sync with the smart system evolution for powering various sensor nodal network. Using natural wind, the 3D printed wind actuated venturi triboelectric energy harvester converts ambient mechanical energy into electricity. This simple and compact device produces an optimum average power of 1.5 mW and produces a maximum output power density of 2850 mW.m-2 (peak power output of 4.5 mW), which is much higher than the existing reports that use larger surface area at higher wind velocity. Extensive material testing and future implementation in an array of applications aids for environment friendly energy production and increase the role of triboelectric nanogenerator in autonomous applications.

This paper shows that the well-know chalcogenide Ge 2 Sb 2 Te 5 (GST) in its amorphous state may be advantageously used as solid electrolyte material to fabricate Conductive-Bridge Random Access Memory (CBRAM) devices. GST layer was sputtered on preliminary inkjet-printed silver lines acting as active electrode on either silicon or plastic substrates. Whatever the substrate, the resistance switching is unambiguously attested at a nanoscale by means of conductive-atomic force microscopy (C-AFM) using a Pt-Ir coated tip on the GST surface acting as a passive electrode. The resistance change is correlated to the appearance or disappearance of concomitant hillocks and current spots at the surface of the GST layer. This feature is attributed to the formation/dissolution of a silver-rich protrusion beneath the AFM tip during set/reset operation. Beside, this paper constitutes a step toward the elaboration of crossbar memory arrays on flexible substrates since CBRAM operations were demonstrated on W/GST/Ag crossbar memory cells obtained from an heterogeneous fabrication process combining physical deposition and inkjet-printing.

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