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Materials science is nowadays facing challenges in optimizing properties of materials which are needed for numerous technological applications and include, but are not limited to, mechanics, electronics, optics, etc. The key issue is that for emerging applications materials are needed which incorporate certain properties from polymers or biopolymers and metals or ceramics at the same time, thus fabrication of functional hybrid materials becomes inevitable. Routes for the synthesis of functional hybrid materials can be manifold. Among the explored routes vapor phase processing is a rather novel approach which opts for compatibility with many existing industrial processes. This topical review summarizes the most important approaches and achievements in the synthesis of functional hybrid materials through vapor phase routes with the goal to fabricate suitable hybrid materials for future mechanical, electronic, optical or biomedical applications. Most of the approaches rely on atomic layer deposition (ALD) and techniques related to this process, including molecular layer deposition (MLD) and vapor phase infiltration (VPI), or variations of chemical vapor deposition (CVD). The thus fabricated hybrid materials or nanocomposites often show exceptional physical or chemical properties, which result from synergies of the hybridized materials families. Even though the research in this field is still in its infancy, the initial results encourage further development and promise great application potential in a large variety of applications fields such as flexible electronics, energy conversion or storage, functional textile, and many more.

robustness to mechanical stress. The combination of these two properties is typically found in inorganic materials such as metals and metal oxides, therefore inorganic materials which are able to selfrecover are in high demand. [3] Examples of self-healing materials for applications in electronics and related fields are scarce. The few existing ones describe materials that can restore their crack-degraded conductivity, [4] including semiconducting polymers, [5] conductive polymer networks, [6,7] microchannels, and microcapsules filled with Ga-based liquid metal alloys, [8,9] or metal-containing solutions, [10] and ionic hydrogels. [11,12] Further progress remains challenging, primarily because of the lack of feasible healing agents and suitable ways to supply them to the damaged site. In theory, the most logical way to construct self-healing materials is by the entrapment of reactive precursors within the bulk material which reacts only upon exposure to air, for example at a damaged site. Unfortunately, this is a complex and potentially dangerous approach due to the reactivity of the applied chemicals. [10] We aim to widen the pool of self-healing materials from soft matter toward metal oxides (MeOs), including the highly demanded transparent conductive oxides (TCOs). MeOs are typically very inert in ambient conditions. Healing cracks in MeOs by recrystallization would require considerable energy investment. If a device contains polymers, for example as a substrate in the case of flexible electronics, such an energy input will be incompatible with the thermal range of the polymers and is therefore not applicable. Self-healing of inorganic materials and structures could alternatively be realized by loading a polymeric substrate with inorganic nanoparticles (NPs) and enabling their mobility inside the substrate. The spatial distribution of NPs can be tuned by harnessing both enthalpy and entropy. [13][14][15][16] In suitable material systems, the NPs can migrate to new damage-induced interfaces, agglomerating and thereby performing self-healing events. [17] However, a polymer coating on inorganic NPs was required in that work, which shielded the NPs and therefore affected their functional properties. [17] An entropy-driven NP reorganization, as described in this work, suggests a promising and safe alternative pathway to allow the healing of metal oxides. As a first step, a system with MeO nanoparticles, well-dispersed inside a preferably polymeric host matrix, is needed. This can be obtained by vapor phase infiltration (VPI) of a polymer with inorganic materials. [18][19][20] The approach will yield a hybrid or nanocomposite polymerinorganic material with an inorganic thin film coating of the same or another MeO, depending on the process setup. [21] This Enabling self-healing of materials is crucially important for saving resources and energy in numerous emerging applications. While strategies for the selfhealing of polymers are advanced, mechanisms for semiconducting inorganic materials are scarce due to the lack ...

Beryllium, being one of the most transparent materials to X-ray radiation, has become the material of choice for X-ray optics instrumentation at synchrotron radiation sources and free-electron laser facilities. However, there are concerns due to its high toxicity and, consequently, there is a need for special safety regulations. The authors propose to apply protective coatings in order to seal off beryllium from the ambient atmosphere, thus preventing degradation processes providing additional protection for users and prolonging the service time of the optical elements. This paper presents durability test results for Be windows coated with atomic-layer-deposition alumina layers run at the European Synchrotron Radiation Facility. Expositions were performed under monochromatic, pink and white beams, establishing conditions that the samples could tolerate without radiation damage. X-ray treatment was implemented in various environments, i.e. vacuum, helium, nitrogen, argon and dry air at different pressures. Post-process analysis revealed their efficiency for monochromatic and pink beams.

We report here the growth and functional properties of silicon-based nanowhisker (NW) diodes produced by the vapor–liquid–solid process using a pulsed laser deposition technique. For the first time, we demonstrate that this method could be employed to control the size and shape of silicon NWs by using a two-component catalyst material (Au/Cu ≈ 60:1). During the NW growth, copper is distributed on the outer surface of the NW, whereas gold sticks as a droplet to its top. The length of NWs is defined by the total amount of copper in the catalyst alloy droplet. The measurements of the electrical transport properties revealed that in contact with the substrate, individual NWs demonstrate typical I – V diode characteristics. Our approach can become an important new tool in the design of novel electronic components.