An improved lifetime can be achieved by exploiting higher intrinsic durability of the materials, or by repairing the deteriorated component and restoring its original properties. Indeed, in the last years, several attempts to improve the lifetime of widespread devices (prosthetics, batteries, solar cells, lighting devices, etc.) were reported. [4-8] However, traditional techniques (welding, gluing, patching) need in situ application of fresh healing materials, and are not applicable to many modern complex devices that require disassembly and targeted operations well beyond the expertise of the final user. Moreover, repair by specialized personnel may be impossible or unsustainable from an economic point of view. To overcome these problems, a radically new strategy that can pave the way for more durable materials is emerging: the concept of selfhealing (SH). [9] This term refers to those smart materials that can automatically restore some, or all, of their functions after having suffered of an external damage that degraded their original properties. This usually has to do with autonomous recovery of physical cracks, but may include a wider range of features prolonging the lifetime of a material/ device, which space from anticorrosion to bactericidal properties. [10,11] By tailoring an appropriate response of the system, it becomes possible to design a material that can respond to various external perturbations and accommodate their eventual disturbance. The idea at the base of this approach is usually defined as biomimetic, since it takes inspiration from nature and mimic it in solving complex technological problems. [12] During the years, many different materials or technologies, naively depicted in Figure 1a, have taken inspiration from nature (as Velcro tape which mimics tiny hooks on bur fruits, naturally ventilated facades that mime termites' mounds, hydrophobic lotus-leaf coatings, and iridescent or adhesive surfaces respectively inspired by butterflies and geckos) and self-healing is not an exception. [13-15] In fact, in nature many organisms are capable of healing damages and of restoring their functionalities: skin, bones, plants, and other living systems can sense any failure and reconstruct the injured biological part which recovers its original functionalities. [16-18] Since these features lengthen the life of natural living beings, analog mechanisms can be exploited in artificial self-healing materials to benefit the Major improvements in stability and performance of batteries are still required for a more effective diffusion in industrial key sectors such as automotive and foldable electronics. An encouraging route resides in the implementation into energy storage devices of self-healing features, which can effectively oppose the deterioration upon cycling that is typical of these devices. In order to provide a comprehensive view of the topic, this Review first summarizes the main self-healing processes that have emerged in the multifaceted field of smart materials, classifying them on the basis of t...

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Lithium metal batteries (LMBs) will be a breakthrough in automotive applications, but they require the development of nextgeneration solid-state electrolytes (SSEs) to stabilize the anode interface. Polymer-in-ceramic PEO/TiO 2 nanocomposite SSEs show outstanding properties, allowing unprecedented LMBs durability and self-healing capabilities. However, the mechanism underlying the inhibition/delay of dendrite growth is not well understood. In fact, the inorganic phase could act as both a chemical and a mechanical barrier to dendrite propagation. Combining advanced in situ and ex situ experimental techniques, we demonstrate that oligo(ethylene oxide)-capped TiO 2 , although chemically inert toward lithium metal, imparts SSE with mechanical and dynamical properties particularly favorable for application. The selfhealing characteristics are due to the interplay between mechanical robustness and high local polymer mobility which promotes the disruption of the electric continuity of the lithium dendrites (razor effect).

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Perovskite solar cells (PSCs) are experiencing tremendous interest due compatibility with solution processing on a wide range of substrates and very high efficiency. The Hole Transport Layer (HTL) plays a...

Doped organic semiconductors play a central role in the development of several innovative optoelectronic and energy harvesting applications. Currently, the realization of thermoelectric generators, which require both hole‐ and electron‐transporting materials with high electrical conductivity, is strongly hindered by the scarce availability of stable solution‐processable n‐dopants and their limited efficiency. Herein, the synthesis of 4‐(1,3‐dimethyl‐2,3‐dihydro‐1H‐benzimidazol‐2‐yl)‐dibenzazepine (IStBI), a novel derivative belonging to the well‐known family of the benzimidazoline compounds, is presented. The functionalization with the planarized and rigid iminostilbene substituent allows, without significantly affecting the compound electronic structure, an efficient intercalation of the dopant molecules inside the ordered regions of thin films of the benchmark n‐type polymer poly(N,N′‐bis‐2‐octyldodecylnaphthalene‐1,4,5,8‐bis‐dicarboximide‐2,6‐diyl‐alt‐5,5′‐2,2′‐bithiophene) P(NDI2OD‐T2). Consequently, a maximum electrical conductivity of (1.14 ± 0.13) × 10−2 S cm−1 is recorded, exceeding by one order of magnitude what previously achieved upon solution doping of the reference P(NDI2OD‐T2) with benzimidazoline derivatives. The thermoelectric power factor is also simultaneously increased. The findings confirm that tailoring of the dopant chemical structure to improve structural interactions with the host semiconductors can be employed as a successful strategy to achieve more effective n‐doping, helping to close the performance gap with p‐type materials.

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