Nicola Calisi

Flexible electronic textiles hold potential applications across various fields, yet current functionalization methods frequently suffer from poor coating uniformity and severe aesthetic alteration. This study addresses these challenges by establishing a multi-analytical approach, based on Raman spectroscopy together with DLS, Zeta potential and XPS measurements, to optimize graphene oxide (GO) precursor selection prior to electrostatic deposition onto cotton fabrics using a polyethyleneimine linker. This coating strategy was inspired by layer-by-layer deposition technique and centrifugation was used to partition a heterogeneous commercial GO precursor into three distinct homogeneous fractions. Raman spectroscopy revealed that centrifugation acts not merely separating GO based on its size but effectively sorts GO sheets based on their chemical functionalization degree. Consequently, this approach allows for the identification of the optimal precursor fraction, balancing sheet dimensions with defect density, to ensure strong functionalization. Overall, this work established a foundational spectroscopic methodology for precursor selection, deposition monitoring and process optimization, which can also be extended to the characterizing and comparison of different commercial GO batches from different industrial suppliers. Finally, micro-Raman mapping and XPS were preliminary applied to verify the textile fiber functionalization.

The development of resin-regolith composites represents a promising In Situ Resource Utilization (ISRU) strategy for future lunar missions. While unsuitable for primary habitat construction due to the payload cost of transporting polymers from Earth, these composites offer a highly efficient solution for manufacturing non-structural, everyday items (e.g., containers, tools, and plant cultivation pots) directly on the Moon via mold–casting. This approach significantly reduces the volume and mass of pre-formed plastic payloads. In this work, the influence of the particle size distribution of a lunar highland simulant (LHS-1E) on the mechanical properties of epoxy-based composites was systematically investigated for such applications. First, the regolith-to-resin ratio was optimized for castability, establishing a maximum regolith content of 60 wt.%. Then, four different size fractions of the simulant were prepared by sieving (>200 µm, 200–100 µm, 100–50 µm, and 200 µm) increased composite porosity, whereas smaller fractions promoted more compact structures. Three-point bending tests showed that intermediate particle sizes (200–100 µm and 100–50 µm) led to enhanced flexural strength, while the smallest particles (200 µm) exhibited superior wear resistance, whereas particle size had negligible effects on the coefficient of friction. Overall, the results demonstrate that both particle size and mineralogical composition significantly influence the performance of regolith–epoxy composites, providing essential guidelines for the in situ manufacturing of functional, non-structural objects for lunar outposts.

We present a tunable nanostructured material platform based on atomic layer deposition (ALD) of nickel oxide and platinum onto titania nanotube arrays (TiNT) embedded in a porous titanium web. The...

The chapter “Materials Science and Engineering Innovation” explores the strategic role of materials research in the Department’s technological development. Through studies on metallic, polymeric, and composite materials, nanostructures, and surface treatments, it examines the relationships between structure, properties, and performance. The integration of experimental characterization, modeling, and industrial applications enables the development of innovative solutions for energy, advanced manufacturing, mobility, and sustainability, strengthening the link between fundamental research and technology transfer.

This study investigates the fabrication of nanostructured chromium thin films via selective dissolution of PVD-deposited Cu–Cr thin films. The effects of the deposition parameters on the structural, chemical, and morphological properties of the films are systematically analyzed. Starting from a thin film composed of 50 wt.% chromium and 50 wt.% copper, deposited onto a substrate pre-heated to 300 °C, we demonstrate that the following dealloying process carried out in a diluted nitric acid solution yields nanostructured chromium films with high porosity, large surface area, enhanced wettability and neglectable copper content. These findings underline the critical influence of the deposition temperature and alloy composition on achieving optimal film properties.

We present an experimental study concerning the interplay between amplified spontaneous emission (ASE) and photoluminescence in polycrystalline thin films (100–300 nm) realized by Radio-Frequency Magnetron Sputtering (RF-MS) without the use of a waveguide configuration. Our results show that the amplification of the spontaneous emission requires only a thickness comparable to the absorption length (≈100 nm). Moreover, the strong ASE signal measured at room temperature shows a peculiar behavior performing a z-scan of the exciting beam waist: increasing the fluence, the decrease of the ASE intensity is accompanied by a significant decrease of the absorption coefficient, indicating the onset of a non-linear process due to multiexciton population (space filling effect) in the film nanocrystallites. Our studies performed with high spectral resolution reveal a modal structure with a significant stability in time, both in the spectral line shape and intensity, from pulse to pulse and demonstrate that CsPbBr3 nanometric films deposited by RF-MS can be efficiently used as active material for coherent light amplification. Moreover, the absorption change detected at high photon fluence can be used for the development of light modulators.

A gold surface is functionalized by chemisorption of the enantiopure N,N′-bis-[2,2′;5′,2″]tert-thiophene-5-yl methylcyclohexane-1,2-diamine (2T3N), a chiral oligothiophene derivative, via overnight incubation in a 2T3N ethanol solution. The Au|2T3N interface is characterized by x-ray photoelectron circular dichroism and comparing x-ray photoemission spectroscopy and electro-desorption results. Charge transmission at the Au|2T3N| solution interface is characterized by recording the cyclic voltammetry of the Fe(III)/Fe(II) reversible redox couple, finding a charge transfer rate constant, k°, variation from 1 × 10−1 to 3.3 × 10−2 cm s−1, when comparing the bare Au and the Au|2T3N interfaces, respectively. The “anomalous” high value of k° found for the chiral Au|2T3N interface can be rationalized on the basis of the chiral-induced spin selectivity effect, as further proved by magnetic–conductive atomic force microscopy measurements at room temperature. A spin polarization of about 30% is found.

Spintronics is a new branch of electronics in which the spin of the electrons as well as their charge is manipulated to produce a desired outcome. Spintronic devices are particularly attractive for memory storage and magnetic sensor applications, and potentially for quantum computing where the electron spin would represent a bit of information. Nowadays many efforts are made to increase the efficiency and lower the production costs of these materials, among others the use of molecular inorganic compounds and cheap preparation techniques [1]. Most of these layers are synthesized with physical and/or vapor phase techniques [2] which allow to obtain materials with a very few defects, but which are complex to manage and typically very expensive. For this reason, in this study we have searched for a way to electrochemically deposit a compound with interesting spintronic properties in the aqueous medium. In fact, electrodeposition is notoriously a very cheap, versatile and easily scalable technique. With this purpose Mn-As system was selected thanks to its good magnetic and transport properties to be used as building blocks for spin valve [3]. MnAs has potential applications in spintronics, for electrical spin injection into GaAs and Si based devices [4] and DFT simulations predict that Mn₂As and Mn₃As have a low magnetization saturation and a high spin polarization at the Fermi-level [5]. Starting from MnSO₄ and NaAsO₂ precursors solutions with various concentrations, supporting electrolytes and pH were tested. The electrochemical behaviour of the precursors was investigated with cyclic voltammetries and both potentiostatic as well as galvanostatic deposition were carried out. The deposits obtained were morphologically and compositional characterised with scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray fluorescence spectroscopy (XRF), the chemical states were analysed with X-ray photoelectron spectroscopy (XPS), the crystalline structure was investigated with X-ray diffraction measurements (XRD). The preliminary magnetic and transport measurements evidence the promising properties of this deposition process to provide spinfiltering materials. The authors acknowledge Regione Toscana POR CreO FESR 2014-2020 – azione 1.1.5 sub-azione A1 – Bando 1 “Progetti Strategici di ricerca e sviluppo” which made possible the project “RAM-PVD” (CUP 3647.04032020.157000057_1225). References [1] M. Innocenti et al., Journal of Electroanalytical Chemistry 2020, 856, 113705, doi: 10.1016/j.jelechem.2019.113705 [2] M. Yuzuri et al., JJournal of the Physical Society of Japan, 1960, 15, 1845-1850, doi: 10.1143/JPSJ.15.1845 [3] T. Graf et al., Progress in Solid State Chemistry 2011, 39, 1-50, doi: 10.1016/j.progsolidstchem.2011.02.001 [4] C. Mocuta et al. Scientific Reports 2017, 7, 16970, doi: 10.1038/s41598-017-17251-y [5] Heusler database: http://heusleralloys.mint.ua.edu/

Nontoxic all-inorganic perovskites are among the most promising materials for the realization of optoelectronic devices. Here, we present an innovative way to deposit lead-free, totally inorganic Cs₃Bi₂I₉ perovskite from vapor phase. Taking use of a magnetron sputtering system equipped with a radiofrequency working mode power supply and a single target containing the correct ratio of CsI and BiI₃ salts, it was possible to deposit a Cs₃Bi₂I₉ perovskitic film on silicon and soda-lime glass. The target composition was optimized to obtain a stoichiometric deposition, and the best compromise was found with a mix enriched with 20% w/w of CsI. Secondly, the effect of post-deposition thermal treatments (150 °C and 300 °C) and of the deposition on a preheat substrate (150 °C) were evaluated by analyzing the chemical composition, the morphology, the crystal structure, and the optical properties. The thermal treatment at 150 °C improved the uniformity of the perovskite film; the one at 300 °C damaged the perovskite deposited. Depositing on a preheated substrate at 150 °C, the obtained film showed a higher crystallinity. An additional thermal treatment at 150 °C on the film deposed on the preheated substrate showed that the crystallinity remains high, and the morphology becomes more uniform.