Atomic layer deposited ZnO films on stainless steel for biomedical applications

Abstract

The main goal of carried out tests were the impact of physicochemical properties of surface layers on the course of processes taking place on the surface of implants made of metallic biomaterials used in the bone system. As a precursor of ZnO, diethylzinc (DEZ) has been used, which reacted with water enabling the deposition of thin films. The chamber temperature was as follows—T = 200°–300 °C. The number of cycles was 500, 1000, and 1500. In the first stage, pitting corrosion test was carried out. Corrosion resistance has been tested under conditions simulating tissue environment. Moreover, the created layers were tested using electrochemical impedance spectroscopy (EIS). The conducted electrochemical tests showed the beneficial effect of the ZnO layer on the substrate made of 316 LVM steel, as evidenced by the obtained parameters describing the corrosion resistance. Furthermore, tests were performed on mechanical properties (scratch test), surface morphology (SEM and AFM method), and physical properties (wettability and thickness layers) for samples with different surface treatments. The investigations of the surface morphology of the applied ZnO layer using the ALD method showed a tendency to inherit the substrate independently of the used application parameters. On the other hand, the tests of adhesion to the substrate showed that the number of cycles of the application process has a fundamental impact on the adhesion of the applied layer to the substrate. Summarizing tests have clearly shown that the number of cycles and temperature in the case of the ZnO coating is significant and positively influences the increase of electrochemical, mechanical, and physical properties of layers.

Functional Pyromellitic Diimide as a Corrosion Inhibitor for Galvanized Steel: An Atomic-Scale Engineering

“…A thin layer of zinc oxide (ZnO) formed on the coated zinc surface on exposure to the atmosphere. Also, atomic layer deposition of the ZnO thin film on the steel surface provides good structural and thermal stability. , The ZnO film forms zinc hydroxide on contact with water/humidity and finally forms zinc carbonate on exposure to atmospheric carbon dioxide. Zinc carbonate is highly insoluble in water and forms a gray film on the surface.…”

Taguchi method and Box-Behnken design approach for process parameter optimization of magnetite (Fe3O4) coating developed on stainless steel 410 grade by hot alkaline treatment

“…15 The ALD methodology has also been adopted to develop a thin film zinc oxide coating on surgical scalpels made of SS at a reactor chamber temperature of 200°C to replace the wide usage of disposable scalpels in hospitals. 16,17…”

“…15 The ALD methodology has also been adopted to develop a thin film zinc oxide coating on surgical scalpels made of SS at a reactor chamber temperature of 200°C to replace the wide usage of disposable scalpels in hospitals. 16,17 Studies also have been conducted on blackening steel for applications other than surgical instruments. A black coating on Fe360 low carbon steel, developed by hot and cold immersion treatments in aqueous solutions of different compositions, produced a protective layer against corrosion as well as enhanced aesthetics.…”

Application of ALD Thin Films on the Surface of the Surgical Scalpel Blade

“…Its main advantages include the low temperature of the process, thanks to which it is possible to deposit coatings on steel elements after hardening without fear of its tempering or loss of properties. Functional coatings are also often deposited by chemical vapor deposition (CVD) methods [11,12]. The search for a method that would combine good layer adhesion and not too high process temperatures, enabling the coating of hardened substrates, led to the development of the atomic layer deposition (ALD) method, considered a variant of the CVD method.…”