A supramolecular-gel-based twenty-two-member sensor array has been created by introducing well-designed multi-competitive binding interactions into a supramolecular gel.

A novel anion sensor array based on supramolecular metallogels has been developed. It could accurately identify CN(-), SCN(-), S(2-) and I(-) in water. Interestingly, this sensor array is based on a novel design approach termed "competitive coordination control AIE mode" to develop anion-responsive gels which need only one synthesized gelator G1.

Aggregation-induced emission luminogens (AIEgens) have attracted increasing attention in recent years on account of their attribute of overcoming the aggregation-caused quenching (ACQ) phenomenon of conventional organic fluorophores. Despite their remarkable advantages and great developments, most organic AIEgens exhibit broad emission spectra with the full width at half-maxima (FWHM) over 100 nm, which is to the disadvantage of their practical applications. Herein, supramolecular polymeric AIE materials with brighter fluorescence and narrower emission band (higher color purity) than conventional AIEgens were developed by taking advantage of the light-harvesting strategy. These AIE materials, including nanoparticles, microfibers, and thin films, were fabricated from supramolecular polymers comprising quadruple hydrogen-bonded monomer tetraphenylethylene (TPE) and borondipyrromethene (BODIPY) as antenna chromophores and as energy acceptors, respectively. The excitation energy collected by TPE molecules was efficiently transferred to the BODIPY, resulting in up to 6-fold enhanced fluorescence intensity and narrowed emission band with FWHM decreasing from 148 to 32 nm. The resulting nanoparticles showed ∼5-fold higher brightness than commercial quantum dots. The highly fluorescent nanoparticles were successfully applied for in vitro and in vivo fluorescence and chemiluminescence imaging, showing superior imaging performance to conventional AIE nanoparticles.

Structural modifications are a successful and commonly used approach to tune the emission properties of diverse fluorophores, but extending this approach to heavy-atom-free persistent luminophores has so far been unsuccessful. Here we employed a novel strategy to demonstrate triplet-triplet energy transfer from an organic room-temperature phosphor (RTP) with persistent luminescence to an organic molecule with thermally activated delayed fluorescence (TADF). We illustrated this approach by preparing heavy-atom-free composite crystals of an RTP with a long-lifetime emission and a red emissive organic fluorophore with TADF to yield materials with emission above 650 nm. The emission arose from the triplet excited state of an acceptor undergoing thermally activated reverse intersystem crossing (RISC) to the emissive S 1 state. Such composite crystal is the first organic material with persistent TADF, achieved by triplet-triplet energy transfer.

This paper describes a rational approach for reproducibly patterning single Au nanoparticles, 15-20-nm diameter, on silicon wafer substrates. The approach uses scanning probe oxidation (SPO) to pattern silicon oxide nanodomain arrays on silicon substrates modified with octadecyltrimethoxysilane (OTS). It was usually found using aminopropyltrimethoxysilane (APS) that Au nanoparticles only assembled at the domain boundaries probably because of asymmetrically distributed hydroxyl groups. To generate uniformly distributed hydroxyl groups on oxide domains, we employed a two-step treatment to etch and oxidize the substrate. With this treatment, oxide domains consistently attached Au nanoparticles to maximum capacity. Single Au nanoparticles were readily patterned by fabricating oxide nanodomains with a diameter below 30 nm. We also investigated the deposition of APS on OTS monolayers, which resulted in the assembly of Au nanoparticles outside of the oxide domains, and proposed two alternative methods to inhibit it.

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By rationally introducing Ca(2+) and Fe(3+) into a supramolecular gel, a bimetal-gel CaFeG was prepared. CaFeG could reversibly "turn-on" its fluorescence upon sensing H2PO4(-) with specific selectivity under gel-gel states through the competitive coordination of Ca(2+) and Fe(3+) with gelators and H2PO4(-). Thus, CaFeG could act as a H2PO4(-) test kit and could be utilised in rewritable security display materials.

Through the rational introduction of the multi self-assembly driving forces and F(-) sensing sites into a gelator molecule, low-molecular-weight organogelators L1 and L2 were designed and synthesized. L1 and L2 showed excellent gelation ability in DMF and DMSO. They could form stable organogels (OGL1 and OGL2) in DMF and DMSO with very low critical gelation concentrations. OGL1 and OGL2 could act as anion-responsive organogels (AROGs). Unlike most of the reported AROGs showing gel-sol phase transition according to the anions' stimulation, OGL1 could colorimetrically sense F(-) under gel-gel states. Upon addition of F(-), OGL1 showed dramatic color changes, while the color could be recovered by adding H(+). Moreover, OGL1 showed specific selectivity for F(-), other common anions and cations could not lead to any similar response. What deserves to be mentioned is that the report on specific sensing of anions under gel-gel states is very scarce. The gel-gel state recognition can endow the organogel OGL1 with the merits of facile and efficient properties for rapid detection of F(-). Therefore, OGL1 could act as a F(-) responsive smart material.