The effect of both a RF sputtered Al-doped ZnO (AZO) thin film seed layer onto a FTO/glass substrate and its growth time onto the morphological, structural and optical properties of the resulting electrochemically grown ZnO nanorod arrays (NRAs) have been studied. ZnO NRs grown onto the different AZO seed layers exhibit smaller mean diameter and length than those grown onto a bare FTO/glass substrate, but ZnO NR density presents an opposite behavior, by using an AZO seed layer ZnO nanorod density can be increased by a factor of six. ZnO nanorods are highly crystalline with a wurtzite hexagonal structure and with a preferential growth perpendicular to the substrate. The c-axis of most of the ZnO NRs grown onto an AZO seed layer is aligned within ±6° from the substrate surface normal. Both NRAs mean length and density increases light scattering, without greatly affecting the spectra shape. The diffuse reflectance intensity is more sensitive to NR density variations than to length or diameter variations. NR diameter affects directly the shape of these diffuse reflectance spectra: they red-shifts and broadens when NR mean diameter increases. A small influence in the UV edge due to size quantization may be also present.

CdS quantum dots (QDs) decorated ZnO nanorod (NR) arrays were fabricated by a two-step method. The first step consisted in electrochemical growth of single-crystalline ZnO NR arrays, followed by the novel spin-coating assisted SILAR method for decorating the ZnO NRs with CdS QDs. Structural, morphological and optical characterization of CdS QDs/ZnO NR arrays were done. ZnO NRs had a single crystal wurtzite structure growing along the c-axis. The decorated CdS QDs had a quasi-spherical shape with a mean diameter of about 5 nm. The increase of CdS content produces an increase in the visible part of the absorption spectrum. Bandgap energy values for ZnO between 3.26–3.29 eV were obtained. For CdS the measured absorption edge values are between 2.35–2.65 eV (decreasing with the number of coating cycles). Numerical simulations based on effective medium approximation were done to verify these features. The Urbach tail parameter in CdS absorption edge is between 44–52 meV. The photovoltaic performance of ZnO and CdS QDs/ZnO NRs have been evaluated in a photoelectrochemical solar cell configuration with a polysulfide electrolyte under white illumination. The decoration of ZnO NRs with CdS QDs leads to a cell performance of J_SC = 2.67 mA/cm², V_OC = 0.74 V, FF = 0.30 and η = 1.48%.

The fatigue life of metals manufactured via laser-based powder bed fusion (L-PBF) highly depends on process-induced defects. In this context, not only the size and geometry of the defect, but also the properties and the microstructure of the surrounding material volume must be considered. In the presented work, the microstructural changes in the vicinity of a crack-initiating defect in a fatigue specimen produced via L-PBF and made of AISI 316L were analyzed in detail. Xenon plasma focused ion beam (Xe-FIB) technique, scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD) were used to investigate the phase distribution, local misorientations, and grain structure, including the crystallographic orientations. These analyses revealed a fine grain structure in the vicinity of the defect, which is arranged in accordance with the melt pool geometry. Besides pronounced cyclic plastic deformation, a deformation-induced transformation of the initial austenitic phase into α’-martensite was observed. The plastic deformation as well as the phase transformation were more pronounced near the border between the defect and the surrounding material volume. However, the extent of the plastic deformation and the deformation-induced phase transformation varies locally in this border region. Although a beneficial effect of certain grain orientations on the phase transformation and plastic deformability was observed, the microstructural changes found cannot solely be explained by the respective crystallographic orientation. These changes are assumed to further depend on the inhomogeneous distribution of the multiaxial stresses beneath the defect as well as the grain morphology.