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Black glasses are amorphous materials based on silicon oxycarbide. The use of precursors in the form of ladder-like silsesquioxanes enables the control of the amount of carbon ions in the glass network by adjusting ratios of T to D structural units in precursors. In this study, four different sols precursors of four different layers of black glasses on titanium substrates were prepared. The materials were analyzed with the use of various spectroscopic and microscopic methods. Formation of continuous and hermetic layers resistant to corrosion was proven. The black glasses layers were examined as materials for biomedical applications. Therefore, preliminary tests of their bioactivity and biocompatibility were performed. The best results were obtained for the material of lower contribution of carbon ions. [ABSTRACT FROM AUTHOR]

Recent years have seen the dynamic development of methods for functionalizing the surface of implants using biomaterials that can mimic the physical and mechanical nature of native tissue, prevent the formation of bacterial biofilm, promote osteoconduction, and have the ability to sustain cell proliferation. One of the concepts for achieving this goal, which is presented in this work, is to functionalize the surface of NiTi shape memory alloy by an atypical glass-like nanocomposite that consists of SiO2-TiO2 with silver nanoparticles. However, determining the potential medical uses of bio(nano)coating prepared in this way requires an analysis of its surface roughness, tribology, or wettability, especially in the context of the commonly used reference coat-forming hydroxyapatite (HAp). According to our results, the surface roughness ranged between (112 ± 3) nm (Ag-SiO2)—(141 ± 5) nm (HAp), the water contact angle was in the range (74.8 ± 1.6)° (Ag-SiO2)—(70.6 ± 1.2)° (HAp), while the surface free energy was in the range of 45.4 mJ/m2 (Ag-SiO2)—46.8 mJ/m2 (HAp). The adhesive force and friction coefficient were determined to be 1.04 (Ag-SiO2)—1.14 (HAp) and 0.247 ± 0.012 (Ag-SiO2) and 0.397 ± 0.034 (HAp), respectively. The chemical data showed that the release of the metal, mainly Ni from the covered NiTi substrate or Ag from Ag-SiO2 coating had a negligible effect. It was revealed that the NiTi alloy that was coated with Ag-SiO2 did not favor the formation of E. coli or S. aureus biofilm compared to the HAp-coated alloy. Moreover, both approaches to surface functionalization indicated good viability of the normal human dermal fibroblast and osteoblast cells and confirmed the high osteoconductive features of the biomaterial. The similarities of both types of coat-forming materials indicate an excellent potential of the silver-silica composite as a new material for the functionalization of the surface of a biomaterial and the development of a new type of functionalized implants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A protective coating based on SiAlOC glasses was applied on the Crofer 22APU steel. • The outstanding improvement in the oxidation resistance was obtained. • Raman Confocal Imaging was applied to determine the structure of oxidized samples. • The SiAlOC coating entrapped nucleating phases, hence suppression of diffusion. • The formation of Si-O-Cr bridges was established as mechanism. In this work, the potential of using Polymer Derived Ceramics based on SiAlOC glasses in the form of protective thin layers was demonstrated on Ferritic Stainless Steel (FSS) Crofer 22APU steel, an alloy often used for intermediate- and low-temperature Solid Oxide Fuel Cells (SOFC's) interconnects. Microstructural features were investigated by the detailed analysis combining Electron Probe Micro Analysis (EPMA) and Raman Confocal imaging (surface imaging and depth profiling), which revealed the formation of Si-O-Cr bridges, believed to play a crucial role to slow down oxidation of the steel. Additionally, the positive role of aluminum introduced into the SiOC system, which enhances the suppression of the degradation by transport processes. The most crucial value of such findings is the formation of a flexible coating material (SiAlOC glasses) that may be applied on a wide range of FSSs increasing their heat resistance. The application of the combination of methods to determine both chemical (EPMA) and phase (Raman) composition of a multi-layered complex system is also demonstrated. [ABSTRACT FROM AUTHOR]