10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Controlling the Structure and Morphology of Functional Nanoporous Films Fabricated by Direct Deposition of Nanoparticles from Liquid Flame Spray (LFS)
JYRKI M. MÄKELÄ, Janne Haapanen, Paxton Juuti, Miika Sorvali, Markus Nikka, Elham Baniadam, Tampere University of Technology, Tampere, Finland
Abstract Number: 1696 Working Group: Materials Synthesis
Abstract Nanoparticles can be used as building blocks to fabricate larger entities of material, such as highly porous thin films and other types of deposits, which maintain high surface area of nanoparticles and typically possess the exquisite nanostructure, have high purity, tailored properties, controlled composition, degree of oxidation and particle size. Nanoporous thin films are used in gas sensing, energy storage, catalysis, pharmaceutics, biotechnology, etc. Also bulk and roll-to-roll material surface modification has been performed using porous nanoparticle thin films, resulting in superhydrophobic, superhydrophilic, anti-icing, anti-fogging, and antibacterial properties for the material.
We define Liquid Flame Spray (LFS) as one type of flame spray pyrolysis techniques to generate aerosol nanoparticles, based on combining a spray of liquid precursor droplets and a flame where the precursor evaporates, reacts and nucleates into nanoparticulate form. LFS, in particular, operates using hydrogen and oxygen as the combustion gas and oxidizing gas, respectively. The most common nanoparticle materials are noble metals, metal oxides and their mixtures, with nanoparticle size varying within the range 2-200 nm.
Recently LFS has been applied to several types of functional coatings by depositing the nanoparticles directly from the LFS flame to the substrate. Practical applications are numerous, but unfortunately the resistance of the nanoparticle film against wear is still relatively poor, for the time being. We present studies on solutions to strengthen the structure of these porous nanoparticle layers either as in situ process during the deposition or as post-treatment after the deposition. We have considered e.g. adding of binders, sintering, compression, and modifying of nanoparticle composition, to fix nanoparticles in place, still without losing the nanostructure and superior functionality.