Vk 150k

The surface morphology of the specimens was examined by scanning electronic microscopy (SEM, JSM-IT500HR, JEOL, Tokyo, Japan) and confocal laser scanning microscopy (CLSM, VK-150K, Keyence, Osaka, Japan). X-ray photoelectron spectroscopy (XPS, K-Alpha, Thermo Scientific, Waltham, MA, USA) was employed to analyze the surface composition of the samples with a monochromatic Al Kα X-ray source.

Scanning electron microscopy (SEM, Carl Zeiss Jena, Oberkochen, Germany) images were studied on a Merlin Zeiss microscope operated at 3 kV. The chemical composition of the porous CuNi film was determined by energy-dispersive X-ray spectroscopy (EDX, Carl Zeiss Jena, Oberkochen, Germany) at 10, 12, 15, and 18 kV, and 15 kV for fully dense CuNi film. X-ray diffraction (XRD, Panalytical B. V., Almelo, The Netherlands) patterns of the CuNi films were recorded with a Philips X’Pert diffractometer in the 40–56° 2θ-range (step size = 0.03°, step time = 2 s) using Cu Kα radiation (λ = 0.15257 nm). Average crystallite size and phase percentages were estimated using the Rietveld full-pattern fitting procedure (GSAS software, EXPGUI, B.H.ToBy, Gaithersburg, USA version). 3D imaging software (VK-H1XAC, VK-150K, Keyence, Osaka, Japan version) was used to measure the surface roughness. LAUDA Scientific GmbH’s LSA-100 is a surface analyzer (Lauda-Königshofen, Germany) which was used to determine the contact angles for the porous surfaces and the fully dense surfaces. The 2 μL water droplets were utilized for the measurements of static contact angles at room temperature. The values reported are average of three measurements made on different areas of the sample surface.