Mattia Alberto Lucchini

Continuous Polyol Synthesis of Metal and Metal Oxide Nanoparticles Using a Segmented Flow Tubular Reactor (SFTR).

Over the last years a new type of tubular plug flow reactor, the segmented flow tubular reactor (SFTR), has proven its versatility and robustness through the water-based synthesis of precipitates as varied as CaCO3, BaTiO3, Mn(1−x)NixC2O4·2H2O, YBa oxalates, copper oxalate, ZnS, ZnO, iron oxides, and TiO2 produced with a high powder quality (phase composition, particle size, and shape) and high reproducibility. The SFTR has been developed to overcome the classical problems of powder production scale-up from batch processes, which are mainly linked with mass and heat transfer. Recently, the SFTR concept has been further developed and applied for the synthesis of metals, metal oxides, and salts in form of nano- or micro-particles in organic solvents. This has been done by increasing the working temperature and modifying the particle carrying solvent. In this paper we summarize the experimental results for four materials prepared according to the polyol synthesis route combined with the SFTR. CeO2, Ni, Ag, and Ca3(PO4)2 nanoparticles (NPs) can be obtained with a production rate of about 1–10 g per h. The production was carried out for several hours with constant product quality. These findings further corroborate the reliability and versatility of the SFTR for high throughput powder production.

Titania-Cellulose Hybrid Monolith for In-Flow Purification of Water under Solar Illumination

In this work, we report a versatile approach for the development of an in-flow purification water system under solar illumination. Cellulose nanofibrils (CNFs) were impregnated with TiO2 nanoparticles using water as a solvent to obtain hybrid CNF/TiO2 monoliths with 98% porosity. The opposite surface potential enables an electrostatically induced direct conjugation between TiO2 and CNFs. Scanning electron microscopy analysis of the surface morphology of the CNF/TiO2 monolith shows a homogeneous dense coating of titania nanoparticles onto the interconnected nanofibril network, providing a Brunauer-Emmett-Teller surface area of about 80 m2·g-1 for the hybrid monolith. Furthermore, compression tests reveal a good shape recovery after unloading, thanks to the highly flexible and mechanically stable three-dimensional structure. Finally, the CNF-based hybrids were tested as catalysts for the decomposition of organic pollutants under solar illumination. The tests were performed using a continuous flow reactor with a customized holder, allowing the solution to pass through the monolith. The results reveal a good photocatalytic activity and a long-term stability of the hybrid CNF/TiO2 monolith toward the decomposition of methyl orange and paracetamol. These features provide a proof of concept for the applicability of the hybrid CNF/TiO2 monoliths for in-flow purification of water under solar illumination, not only for model dyes but also for organic pollutants of high practical relevance.

Tailoring the phase of Li–Al–O nanoparticles by nonaqueous sol–gel chemistry

A facile nonaqueous sol–gel synthesis for Li–Al–O nanoparticles with tunable stoichiometry and phase purity has been developed. Adjusting the reaction conditions, γ-Al2O3, α-Al2O3, LiAl5O8, β-LiAlO2, and γ-LiAlO2 nanoparticles can be synthesized. For the first time, the synthesis of phase-pure nanoscaled β-LiAlO2 is obtained at low temperature. All the products were characterized by X-ray powder diffraction, Fourier-transformed infrared, small-angle X-ray scattering, transmission electron microscopy/scanning electron microscopy, nitrogen sorption and elemental analysis. The extensive characterization points out some main features for the products: phase purity, nanoscale size, high surface area, good thermal stability, and good dispersion in ethanol. These properties are rarely combined in a single product, making the proposed protocol an important tool for the future applications of Li–Al–O nanoparticles in the field of catalysis and absorptive materials.Graphical AbstractNonaqueous sol–gel chemistry: an easy and versatile protocol for compositionally tuneable, phase-pure, and high surface area Li–Al–O nanoparticles.