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Single phase Cd0.6Zn0.4Te (CdZnTe) films of 1 μm thickness were deposited by radio frequency planar magnetron sputter deposition on commercial soda lime glass samples coated with fluorinedoped tin oxide and cadmium sulphide (CdS). The stack was then treated with cadmium chloride (CdCl2) at different temperatures using a constant treatment time. The effect of the CdCl2 treatment was studied using optical, materials, and electrical characterization of the samples and compared with the as-deposited CdZnTe film with the same stack configuration. The band gap deduced from Tauc plots on the as-deposited CdZnTe thin film was 1.72 eV. The deposited film had good crystalline quality with a preferred orientation along the {111} plane. After the CdCl2 treatment, the absorption edge shifted toward longer wavelength region and new peaks corresponding to cadmium telluride (CdTe) emerged in the x-ray diffraction pattern. This suggested loss of zinc after the CdCl2 treatment. The cross sectional transmission electron microscope images of the sample treated at 400 °C and the energy dispersive elemental maps revealed the absence of chlorine along the grain boundaries of CdZnTe and residual CdTe. The presence of chlorine in the CdTe devices plays a vital role in drastically improving the device performance which was not observed in CdZnTe samples treated with CdCl2. The loss of zinc from the surface and incomplete recrystallization of the grains together with the presence of high densities of stacking faults were observed. The surface images using scanning electron microscopy showed that the morphology of the grains changed from small spherical shape to large grains formed due to the fusion of small grains with distinct grain boundaries visible at the higher CdCl2 treatment temperatures. The absence of chlorine along the grain boundaries, incomplete recrystallization and distinct grain boundaries is understood to cause the poor performance of the fabricated devices. [ABSTRACT FROM AUTHOR]

To achieve long term success of orthopedic implants, it is critical to have a successful integration of bone and implant material. To accomplish this, various surface modifications have been investigated in research. Even though titania nanotubes and copper have individually demonstrated successful stem cell adhesion, proliferation and differentiation, these modifications have not yet been investigated together. In this study, we fabricated copper-modified titania nanotubes and evaluated the adhesion, proliferation and osteogenic differentiation of adipose derived stem cells on these surfaces. Implant surfaces also have to interact with blood after insertion in the body. Several studies have shown the importance of blood clots on material surfaces and their influence in differentiation of cells. Hence, blood clotting properties of modified surfaces were also investigated through whole blood clotting, and platelet adhesion and activation. The copper-modified titania nanotube surfaces demonstrated increased differentiation of adipose derived stem cells towards osteogenic lineage as well as enhanced blood clotting properties, thus they can be used as a potential surface for orthopedic implants., Competing Interests: All the authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)