Mika Vähä-Nissi

Atomic Layer Deposition of Thin Inorganic Coatings onto Renewable Packaging Materials

Biopolymers play still a relatively minor role in the packaging material markets. For this to grow further there are problems to be solved, such as inadequate barrier properties and moisture sensitivity. Atomic layer deposition (ALD) is one potential solution. Atomic layer deposition is a layer-by-layer thin film deposition process based on self-limiting gas-solid reactions. It is well suited for producing pinhole free barrier coatings uniform in thickness at relatively mild process conditions. The purpose of this presentation is to summarize our recent work done concerning atomic layer deposition of thin aluminum oxide layers onto biopolymers.

Atomic layer deposition of Ti-Nb-O thin films onto electrospun fibers for fibrous and tubular catalyst support structures

Here, the authors report on the preparation of core–shell carbon-ceramic fibrous as well as ceramic tubular catalyst supports utilizing electrospinning and atomic layer deposition (ALD). In this paper, ALD of Ti-Nb-O thin films using TiCl4, Nb(OEt)5, and H2O as precursors is demonstrated. According to the time-of-flight-elastic recoil detection analysis and Rutherford backscattering spectrometry, carbon and hydrogen impurities were relatively low, but depend on the pulsing ratio of the precursors. Optimized ALD process was used for coating of sacrificial electrospun polyvinyl alcohol (PVA) template fibers to yield tubular Ti-Nb-O structures after thermal or solution based PVA removal. Another approach utilized 200–400 nm thick carbon fibers prepared by electrospinning from polyacrylonitrile and subsequent thermal treatment.Here, the authors report on the preparation of core–shell carbon-ceramic fibrous as well as ceramic tubular catalyst supports utilizing electrospinning and atomic layer deposition (ALD). In this paper, ALD of Ti-Nb-O thin films using TiCl4, Nb(OEt)5, and H2O as precursors is demonstrated. According to the time-of-flight-elastic recoil detection analysis and Rutherford backscattering spectrometry, carbon and hydrogen impurities were relatively low, but depend on the pulsing ratio of the precursors. Optimized ALD process was used for coating of sacrificial electrospun polyvinyl alcohol (PVA) template fibers to yield tubular Ti-Nb-O structures after thermal or solution based PVA removal. Another approach utilized 200–400 nm thick carbon fibers prepared by electrospinning from polyacrylonitrile and subsequent thermal treatment.