Synthesis and Microstructural Investigations of Organometallic Pd(II) Thiol-Gold Nanoparticles Hybrids

In this work the synthesis and characterization of gold nanoparticles functionalized by a novel thiol-organometallic complex containing Pd(II) centers is presented. Pd(II) thiol,trans, trans-[dithiolate-dibis(tributylphosphine)dipalladium(II)-4,4′-diethynylbiphenyl] was synthesized and linked to Au nanoparticles by the chemical reduction of a metal salt precursor. The new hybrid made of organometallic Pd(II) thiol-gold nanoparticles, shows through a single S bridge a direct link between Pd(II) and Au nanoparticles. The size-control of the Au nanoparticles (diameter range 2–10 nm) was achieved by choosing the suitable AuCl4−/thiol molar ratio. The size, strain, shape, and crystalline structure of these functionalized nanoparticles were determined by a full-pattern X-ray powder diffraction analysis, high-resolution TEM, and X-ray photoelectron spectroscopy. Photoluminescence spectroscopy measurements of the hybrid system show emission peaks at 418 and 440 nm. The hybrid was exposed to gaseous NOxwith the aim to evaluate the suitability for applications in sensor devices; XPS measurements permitted to ascertain and investigate the hybrid –gas interaction

Selecting the Desired Solid Form by Membrane Crystallizers: Crystals or Cocrystals

This work aims to describe a systematic study on the conditions promoting the selective formation of carbamazepine-saccharin cocrystals or single component crystals from water/ethanol solvent mixtures, by using a membrane crystallization process. Results revealed the ability to operate in the proper zone of the phase diagram of the system when opportunely choosing the initial solution conditions and limiting the maximum level of supersaturation by using the membrane-based technology. Control in the selective crystallization of a specific solid form can be achieved by adjusting the solvent evaporation through the micropores of the membrane. Furthermore, the direct correlation between transmembrane flow and polymorphic composition in the case of carbamazepine precipitation confirmed the possibility to produce particular metastable phases upon increasing the supersaturation rate

Self-organization of mono- and bi-modal PbS nanocrystal populations in superlattices

Here the synthesis of distinct monomodal and bimodal PbS nanocrystal (NC) populations, with narrow size-distribution, is reported. The ability to achieve careful control of NC size and size distribution allowed the preparation, in one single synthetic step, of two distinct populations of PbS NCs, with tuneable size ratio. The NC growth was carefully studied in order to gain insight into the mechanism underlying the formation of the mono and bimodal PbS NC families. The synthesized PbS NCs were structurally and chemically characterized, and subsequently used as building blocks for fabricating solid crystal assemblies by solvent evaporation. In particular the role played by different parameters, namely NC size and concentration, dispersing solvent and substrate, on crystallinity, geometry and structure of the obtained solids was systematically investigated. Interestingly the assembly of bimodal PbS NC samples leads to the formation of diverse superlattice structures, with a final geometry dependent on the NC size and the size ratio in the bimodal population. The synthetic procedure was then ultimately responsible of the superlattice structures, through the control of the PbS NC size and size ratio in the bimodal population

Biomimetic calcium phosphate nanoparticles as promising nanocarriers for sustainable agricultura

Trabajo presentado en la 16th NanoSpain Conference (NanoSpain2019), celebrada en Barcelona (España), del 28 al 31 de mayo de 201

Towards a more sustainable viticulture: Foliar application of N-doped calcium phosphate nanoparticles on Tempranillo grapes

The use of nanomaterials for the efficient delivery of active species in viticulture is still an unexplored opportunity. Nitrogen, an essential nutrient for grapevine development and wine quality, is commonly provided in the form of urea. However, the application of conventional fertilisers contributes to nitrate leaching and denitrification, thus polluting groundwater and causing a serious environmental impact. Nanotechnology is offering smart solutions towards more sustainable and efficient agriculture. In the present work, we assessed the efficiency of nontoxic amorphous calcium phosphate (ACP) nanoparticles as nanocarriers of urea (U-ACP) through field experiments on Tempranillo grapevines. Four treatments were foliarly applied: U-ACP nanofertiliser (0.4 kg N/ha), commercial urea solutions at 3 and 6 kg N/ha and a control treatment (water)