As a biocompatible semiconductor composed of abundant elements, ZnO has received a huge interest for a wide variety of electronic, optoelectronic, chemical, and biological sensing applications. Thanks to its high PZ coefficients as a semiconductor, the integration of ZnO into PZ devices such as PZ nano-generators and/or pressure/strain sensors has extensively been considered in the last decade. Moreover, in the shape of NWs grown by the low temperature and surface scalable chemical bath deposition (CBD) technique that is compatible with green chemistry, ZnO exhibits numerous assets originating from its high crystalline quality, its interesting tuneable physical properties, its low-cost applicability into flexible PZ devices, and its possible recyclability. In contrast, the investigation of fundamental issues related to the properties of ZnO NWs has been ignored, to some extent, despite their primary importance.

The main objective of the IMINEN project is thus to investigate nano-sized effects on the PZ coefficients, doping/polarity, and surfaces of ZnO NWs over a diameter range of 10-100 nm, and hence at an ultimate low size. The fabrication of such ZnO NWs will allow to experimentally correlate their physical properties and show their diameter dependence, while providing input parameters for the predictive modelling of the performances of PZ devices. The main goal of this research involves the design, chemical synthesis, and advanced characterization at nanoscale of ordered, resistive, unipolar ZnO NWs with an ultimate low size. The IMINEN project gathers the unique skills of the consortium to strongly deepen the knowledge in the field of PZ devices and target a technological breakthrough.