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Mono-TPE modified POSS molecules, in which the flexible spacers between TPE and POSS moieties control their self-assembly and aggregation, exhibit a unique unadulterated monomer emission in organic solvents as well as an AIE emission in THF/water. [ABSTRACT FROM AUTHOR]

The research on electrochromic conjugated polymers (ECPs) and their devices has gone a long way. They can now perform with a multitude of color variations, high optical contrasts, rapid switching speeds and low power consumption. This review traces the progress of color control, synthetic methods, and the development of building blocks for ECPs. The advances in the integration and optimization of electrochromic devices (ECDs) in terms of their constituting components are presented. The potential of ECDs in numerous applications through the illustration of several prototypes is then highlighted. Finally, the challenges associated with the prospective commercialization of the said devices are discussed. [ABSTRACT FROM AUTHOR]

A microporous hydrogen-bonded organic framework (HOF) derived from a polyhedral oligomeric silsesquioxane (POSS) intermediate and an aggregation-induced emission (AIE) luminogen tetraphenylethene (TPE) derivative has been synthesized and structurally characterized by various methods. This unique HOF exhibits a permanent porosity with a Brunauer–Emmett–Teller (BET) surface area of 101.9 m2 g−1. This HOF could be well dispersed in organic solvents in the form of nanoparticles with a size of a few hundred nanometers. These nanoparticles are highly fluorescent in organic solution, and exhibit a high fluorescence quenching selectivity towards copper ions. Furthermore, the fluorescence of this HOF could be recovered by the removal of copper ions upon addition of cyanide and, more interestingly, this process could be repeated several times without considerably sacrificing the sensing activity towards copper ions. [ABSTRACT FROM AUTHOR]

Aggregation induced emission (AIE) active copolymers P1–P6 with high molecular weights (14 000–17 000) and low polydispersity indices (1.3–1.4) were prepared through copolymerization of N-isopropyl acrylamide (NIPAM) and tetra(phenyl)ethene (TPE)-based acrylate monomers. Copolymers P1–P6 show comparable thermal stability to poly(N-isopropylacrylamide) (PNIPAM), while their glass transition temperatures are higher by 7–9 °C than those of pristine PNIPAM. Copolymers P1–P6 are soluble in common organic solvents as well as in water. They retain a similar thermal sensitivity to PNIPAM, but their lower critical solution temperatures (LCST) are reduced with increase of TPE content. By changing the molar ratio of P1–P6/poly(methacrylic acid) (PMAA) and pH, complexes P1–P6–PMMA were studied by fluorescence spectroscopy and dynamic light scattering (DLS). The complexes are non-emissive in THF, and their fluorescence can be turned on upon addition of water. Moreover, their fluorescence is enhanced with the decrease in pH values due to the formation of interpenetrating polymer networks (IPNs) through inter-polymer hydrogen bonding. Fluorescence spectroscopy and DLS results also reveal that the phase transition behaviour of IPNs upon heating could be significantly modified by pH change. Reduction in the pH value from 7.0 to 4.0 leads to the decrease in LSCT of IPNs by up to 5 °C with respect to PNIPAM. By tuning the pH value to dissociate the formed inter-polymer hydrogen bonds, the formed IPNs would be able to fold cooperatively to a compact structure without a loss of solubility at temperatures below the LCST. Thus, these novel IPNs with AIE active moieties would be used as drug delivery systems, in which the release process could be readily monitored by fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

Low band gap (Eg < 1.5 eV) polycyclic hydrocarbons have become one of the most important types of materials for many applications, for example, as semiconductors in organic field effect transistors (OFETs), as light-harvesting dyes in organic solar cells and photodetectors, as near infrared (NIR) fluorescent probes in high resolution bio-imaging and bio-sensing, and as chromophores in non-linear optics. The benzenoid polycyclic hydrocarbons as nano-sized graphene fragments also serve as perfect model compounds to understand the fundamental structure–property relationship of graphene. The ground state of these molecules can be described as either a closed-shell or an open-shell structure on the basis of their molecular size and edge structure. In this review, a summary will be given on a series of low band gap polycyclic hydrocarbons about their synthesis, physical properties and material applications. [ABSTRACT FROM AUTHOR]