The effect of surface preparation on the protective properties of Al2O3 and HfO2 thin films deposited on cp-titanium by atomic layer deposition

Improvement of Mechanical and Corrosion Properties of Commercially Pure Titanium Using Alumina PEO Coatings

“…Although titanium and its alloys have been extensively used in industry for a wide variety of applications (e.g., aerospace [1,2], automotive [1], medical [1], marine [2], chemical [3] and petrochemical [3] fields) due to their high strength [1], low density [3], corrosion resistance [1] and biological compatibility [3], research efforts have been devoted to enhancing the mechanical and corrosion-resistance properties of pure titanium and titanium alloys through various processing methods, including physical vapor deposition [4], plasma spraying [5], chemical vapor deposition [6], nitriding [7], laser surface engineering [8][9][10], atomic layer deposition [11] and plasma electrolytic oxidation (PEO) [12,13]. PEO involves the electrochemical oxidation of a metal substrate (usually Ti, Zr, Al or Mg) in an aqueous electrolyte in order to generate oxide coatings with improved wear and corrosion-resistance performance [14].…”

Modification of Steel Surfaces with Nanometer Films of Al2O3 and TiO2 Decreases Interfacial Adhesion to Polymers: Implications for Demolding Shape-Engineered Polymer Products

“…52−54 The pre-existence of small particles on the steel can act as preferential nucleation sites for the Al 2 O 3 precursors (Figure 7a), and the growing Al 2 O 3 film mimics the spherical shape of the particles. Interestingly, Spajićet al 54 suggest that the oxygenrich sites and/or grain boundaries on the steel substrate are nucleation sites for the growth of irregular features related to the ALD process. We further analyzed the roughness of the samples using the AFM technique (Figure 7 and Figures S8 and S9).…”

“…This result leads to the conclusion that the observed spheroidal particles on the steel surface are not crystallites of Al 2 O 3 , in opposition to the coarsened particle-like structures in ALD processes of metal oxides on metallic substrates that have been reported in the literature as the formation of a crystalline phase in the film. − The pre-existence of small particles on the steel can act as preferential nucleation sites for the Al 2 O 3 precursors (Figure a), and the growing Al 2 O 3 film mimics the spherical shape of the particles. Interestingly, Spajić et al suggest that the oxygen-rich sites and/or grain boundaries on the steel substrate are nucleation sites for the growth of irregular features related to the ALD process. We further analyzed the roughness of the samples using the AFM technique (Figure and Figures S8 and S9).…”

Preventing Corrosion of Aluminum Metal with Nanometer-Thick Films of Al2O3 Capped with TiO2 for Ultraviolet Plasmonics

“…Atomic layer deposition (ALD) and plasmaenhanced chemical vapor deposition (PECVD) of thin inert layers of metal oxides offer powerful alternative approaches for corrosion protection owing to their ability to deposit dense layers of oxide materials with controlled nanometer thickness and conformal coating at the nanoscale. 50 Alumina (Al2O3), [51][52][53] titania (TiO2) [54][55][56] and hafnia (HfO2) 57,58 are commonly used to protect flat metal surfaces.…”

“…Atomic layer deposition (ALD) and plasma-enhanced chemical vapor deposition (PECVD) of thin inert layers of metal oxides offer powerful alternative approaches for corrosion protection owing to their ability to deposit dense layers of oxide materials with controlled nanometer thickness and conformal coating at the nanoscale . Alumina (Al 2 O 3 ), − titania (TiO 2 ), − and hafnia (HfO 2 ) , are commonly used to protect flat metal surfaces. However, the performance of these coatings has never been tested in the newly developing context of UV plasmonics, i.e., in the presence of UV irradiation and the photogenerated radical species and while keeping the constraint of nanoscale features for the plasmonic nanodevices.…”