title: Real-time monitoring of the solution growth of ZnO nanorods arrays by quartz microbalances and in-situ temperature sensors.
abstract: Wet-chemistry methods have crucial advantages for the synthesis of nanostructures, including simple, low-cost, large-area, and low-temperature deposition on almost arbitrary substrates. Nevertheless, the rational design of improved wet-chemistry procedures is extremely difficult because, in practice, only post-synthesis characterization is possible. In fact, the only methods for on-line monitoring the growth of nanostructures in liquids are complex, expensive and introduce intricate artifacts. Here we demonstrate that electro-mechanically resonating substrates and in-situ temperature sensors easily enable an accurate real-time investigation of reaction kinetics and, in combination with conventional SEM imaging, greatly facilitate the rational design of optimized synthesis procedures; in particular, such a simple approach provides useful insight for the development of processes where one or more key parameters are dynamically adjusted. As a proof-of-concept, first, we accurately characterize a process for fabricating arrays of ZnO nanorods; afterwards, we design a dynamic-temperature process that, in comparison with the corresponding constant-temperature procedure, is almost-ideally energy efficient and results in ZnO nanorods with improved characteristics in terms of length, aspect ratio, and total deposited nanorods mass. This is a major step towards the rational design of dynamic procedures for the solution growth of nanostructures.
authors.affiliation: Department of Electronic Engineering, University of Rome Tor Vergata, Via del Politecnico 1, 00133, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Orsini
authors.affiliation: 1] Department of Electronic Engineering, University of Rome Tor Vergata, Via del Politecnico 1, 00133, Rome, Italy [2] CNR IDASC, Via Fosso del Cavaliere, 100, 00133 Rome, Italy.
authors.forename: Christian
authors.initials: C
authors.lastname: Falconi