physical property differentiating two enantiomers is the direction of rotation of the polarized light. Indeed, the manipulation of polarized light, both in the absorbance and emission mode, is useful in a series of technological applications, such as liquid crystal display (LCD) panels, 3D imaging in biological systems, nonlinear optics, spintronic devices. [5-8] Progresses in the field have been boosted by the increased availability of modern spectroscopic methods. For circular dichroism (CD), which relates to ground-state properties, the commercial availability of the spectrophotometer dates back to the 1960s and has enabled in depth studies of the tertiary structure of proteins. In contrast, circularly polarized luminescence (CPL) spectrophotometers have only been recently commercially available. Nevertheless, CPL gives important additional informations, as it provides information on the excited-state, and luminescence is generally more of interest in terms of materials science and devices. [9] Emissive organic materials have been studied for decades. Among these, organic light-emitting diodes (OLEDs) have reached large-scale commercialization, since they show unique technological advantages with respect to previous technologies: energy-saving, low working voltage, high brightness, and contrast display. Polarized emission and CPL has been the subject of increasing interest. Indeed, circularly polarized OLEDs (CP-OLEDs), based on chiral organic chromophores, have been realized and reported in the recent literature. A variety of chiral organic emitters have been proposed for CPL materials. [10] Aggregation-caused quenching (ACQ) of emission is a common problem that can severely limit the performance of (chiral and achiral) fluorophores in the solid state. The field of emissive dyes has been revolutionized in the early 2000s by Tang's group, which introduced the concept, seemingly counterintuitive at the time, of aggregation-induced emission (AIE). Suitable AIE chromophores (AIEgens) can exhibit strong fluorescence emission in aggregated states, despite being nonemissive in solution. [11] The most frequent mechanism for AIE occurs when AIEgens have freely-rotating groups which, upon excitation, relax back through these rotations instead of releasing energy as light. When they aggregate or crystallize, they become emissive through restricted intramolecular rotation (RIR). Since then, the AIE field literally exploded, and several reports have started to appear on chirality-related CPL emissive dyes. [12] Chirality is becoming increasingly important in the design of organic materials with functional properties, when bulk anisotropy is needed. In the past decades, a plethora of chiral organic materials have been studied and developed. Nanostructures have brought substantial advancement to the realization of organic-molecule-based devices, and the possibilities for solid-state light emission are very promising in view of potential applications. Scientific approaches to the realization of chiral emissive materials are ...

Autonomic self-healing (SH), namely, the ability to repair damages from mechanical stress spontaneously, is polarizing attention in the field of new-generation electrochemical devices. This property is highly attractive to enhance the durability of rechargeable Li-ion batteries (LIBs) or Na-ion batteries (SIBs), where high-performing anode active materials (silicon, phosphorus, etc. ) are strongly affected by volume expansion and phase changes upon ion insertion. Here, we applied a SH strategy, based on the dynamic quadruple hydrogen bonding, to nanosized black phosphorus (BP) anodes for Na-ion cells. The goal is to overcome drastic capacity decay and short lifetime, resulting from mechanical damages induced by the volumetric expansion/contraction upon sodiation/desodiation. Specifically, we developed novel ureidopyrimidinone (UPy)-telechelic systems and related blends with poly(ethylene oxide) as novel and green binders alternative to the more conventional ones, such as polyacrylic acid and carboxymethylcellulose, which are typically used in SIBs. BP anodes show impressively improved (more than 6 times) capacity retention when employing the new SH polymeric blend. In particular, the SH electrode still works at a current density higher than 3.5 A g –1 , whereas the standard BP electrode exhibits very poor performances already at current densities lower than 0.5 A g –1 . This is the result of better adhesion, buffering properties, and spontaneous damage reparation.

A push–pull dye with AIE polymorphism-dependent properties shows mechano-, thermo- and chrono-chromism associated with stimuli-induced surface structural defects.