Abstract. SiC nanowires are of high interest since they combine the physical properties of SiC with those induced by their low dimensionality. For this reason, a large number of scientific studies have been dedicated to their fabrication and characterization as well as to their application in devices. SiC nanowires growth involving different growth mechanisms and configurations was the main theme for the large majority of these studies. Various physical characterization methods have been employed for evaluating SiC nanowire quality. Very low diameter (<10 nm) nanowires as well as nanowires free of planar defects have not been demonstrated and these are some of the main challenges. Another issue is the high unintentional doping of the nanowires that does not allow the demonstration of high performance field effect transistors using SiC nanowires as channel material. On the other hand, the grown nanowires are suitable for field emission applications and to be used as reinforcing material in composite structures as well as for increasing the hydrophobicity of Si surfaces. All these aspects are examined in detail in the different sections of the present paper.

The high‐power conversion efficiency of flexible perovskite photovoltaics (PPV) at low light environment and their low‐cost manufacturing processes, render PPV superior to conventional rigid photovoltaics targeting indoor applications. However, various parameters related to materials, architecture, processing, and indoor characterization need to be optimized further toward improving indoor PPV (iPPV) efficiency, stability, and ecotoxicity. This work provides an overview of the recent progress, trends, and challenges in the field and suggests a holistic approach toward a viable design and integration of iPPVs into Internet of Things (IoT) platforms without any compromise on safety and cost effectiveness. The key impact of selecting proper materials and fabrication techniques, as well as optimizing the active area and architecture is described. Certain peculiarities of the indoor lighting conditions are discussed that can be addressed by proper simulation tools, including the understanding of the charge‐transfer mechanism, the diversification of the lamp types, as well as identifying the requirements for the production, standardization, and installation of iPPVs associated with IoT devices. A multidimensional engineering approach that considers aspects of architecture, light technology, load specifications, materials, processing, safety and cost, is proposed as a path toward accelerating iPPV market uptake for households, businesses, wearables and Industry 4.0 applications.

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Heterostructured material systems devoid of ferroic components are presumed not to display ordering associated with ferroelectricity. In heterostructures composed of transition metal oxides, however, the disruption introduced by an interface can affect the balance of the competing interactions among electronic spins, charges and orbitals. This has led to the emergence of properties absent in the original building blocks of a heterostructure, including metallicity, magnetism and superconductivity. Here we report the discovery of ferroelectricity in artificial tri-layer superlattices consisting solely of non-ferroelectric ndmno 3 /srmno 3 / Lamno 3 layers. Ferroelectricity was observed below 40 K exhibiting strong tunability by superlattice periodicity. Furthermore, magnetoelectric coupling resulted in 150% magnetic modulation of the polarization. Density functional calculations indicate that broken space inversion symmetry and mixed valency, because of cationic asymmetry and interfacial polar discontinuity, respectively, give rise to the observed behaviour. our results demonstrate the engineering of asymmetric layered structures with emergent ferroelectric and magnetic field tunable functions distinct from that of normal devices, for which the components are typically ferroelectrics.

An engineering approach is implemented for the performance and stability enhancement of perovskite solar cells, through the incorporation of bismuth telluride flakes in the electron transport layer (ETL) and as an interlayer on top of the ETL.