Synthesis of Ni/Y2O3 Nanocomposite through USP and Lyophilisation for Possible Use as Coating

Abstract

The Ni/Y2O3 catalyst showed high catalytic activity. Based on this, the aim of this study was to create Ni/Y2O3 nanocomposites powder with two innovative technologies, Ultrasonic Spray Pyrolysis (USP) and lyophilisation. In the USP process, thermal decomposition of the generated aerosols in an N2/H2 reduction atmosphere caused a complete decomposition of the nickel (II) nitrate to elemental Ni, which became trapped on the formed Y2O3 nanoparticles. The Ni/Y2O3 nanocomposite particles were captured via gas washing in an aqueous solution of polyvinylpyrrolidone (PVP) in collection bottles. PVP was chosen for its ability to stabilise nano-suspensions and as an effective cryoprotectant. Consequently, there was no loss or agglomeration of Ni/Y2O3 nanocomposite material during the lyophilisation process. The Ni/Y2O3 nanocomposite powder was analysed using ICP-MS, SEM-EDX, and XPS, which showed the impact of different precursor concentrations on the final Ni/Y2O3 nanocomposite particle composition. In a final step, highly concentrated Ni/Y2O3 nanocomposite ink (Ni/Y2O3 > 0.140 g/mL) and test coatings from this ink were prepared by applying them on a white matte photo paper sheet. The reflection curve of the prepared Ni/Y2O3 nanocomposite coating showed a local maximum at 440 nm with a value of 39% reflection. Given that Ni is located on the surface of the Ni/Y2O3 nanocomposite in the elemental state and according to the identified properties, tests of the catalytic properties of this coating will be performed in the future.

Synthesis of Complex Concentrated Nanoparticles by Ultrasonic Spray Pyrolysis and Lyophilisation

“…For the CCNPs to be used for further analysis, the suspension containing the CCNPs must be dried. Freeze-drying (lyophilisation) of the suspension was performed instead of classical convection drying, to avoid the movement of the liquid during drying and agglomeration of the particles [28,29]. The freeze-drying process itself is limited to the removal of water from the product while the product remains intact, which is why it is most commonly used in the pharmaceutical industry [30,31].…”

“…The drying process must be carried out under optimal conditions to avoid sedimentation, agglomeration, and other side effects. The process conditions, such as primary drying temperature and pressure and secondary drying temperature and pressure, were selected following previous drying cycles for different formulations of nanoparticles [21,29]. These conditions prevented sedimentation, agglomeration (SEM analysis), and collapse of the dried material (the dried material cake was stable and did not collapse).…”

Study of Ni/Y2O3/Polylactic Acid Composite

“…Spray pyrolysis methods consist of five stages: (I) precursor preparation, (II) precursor aerosol generation, (III) aerosol transport, (IV) particle synthesis, and (V) particle collection [ 13 , 14 ]. Precursor solutions that are appropriate for SP methods are metal salts (acetates, bromides, chlorides, hydroxides, nitrates, sulphides) dissolved in water or alcohol [ 15 , 16 , 17 ]. The precursor characteristics (concentration of the salt, viscosity, density, and surface tension) affect the aerosol size distribution and quantity, which, in turn, has a direct impact on particle size and morphology [ 18 ].…”

Layer‐by‐layer preparation of electromagnetic NH2‐SiO2/polypyrrole/Ni nanocomposites, characterization and their electrochemical properties

“…To further widen the application prospect in electrochemical sensors, biosensors, energy storage materials and catalysis, doping of conducting polymers with various nanomaterials, such as carbon, metals or metal oxides, has been attempted 47 . In this regard, doping of PPy with magnetic Ni nanoparticles could be an excellent idea for devising new electroconducting nanocomposite materials with good application prospects in ferrofluids, conducting paints, magnetic recording media, magnetic resonance imaging contrast enhancement, catalysis for water splitting and drug delivery 48–54 …”

“…47 In this regard, doping of PPy with magnetic Ni nanoparticles could be an excellent idea for devising new electroconducting nanocomposite materials with good application prospects in ferrofluids, conducting paints, magnetic recording media, magnetic resonance imaging contrast enhancement, catalysis for water splitting and drug delivery. [48][49][50][51][52][53][54] Until now, very few researchers have described utilization of SiO 2 for hosting conducting PPy. Cheng et al modified mesoporous SiO 2 particles with conducting PPy via in situ polymerization and studied electrorheological character under external electric fields.…”