Sensitive and rapid identification of illicit drugs in a non-contact mode remains a challenge for years. Here we report three film-based fluorescent sensors showing unprecedented sensitivity, selectivity, and response speed to the existence of six widely abused illicit drugs, including methamphetamine (MAPA), ecstasy, magu, caffeine, phenobarbital (PB), and ketamine in vapor phase. Importantly, for these drugs, the sensing can be successfully performed after 5.0 × 105, 4.0 × 105, 2.0 × 105, 1.0 × 105, 4.0 × 104, and 2.0 × 102 times dilution of their saturated vapor with air at room temperature, respectively. Also, presence of odorous substances (toiletries, fruits, dirty clothes, etc.), water, and amido-bond-containing organic compounds (typical organic amines, legal drugs, and different amino acids) shows little effect upon the sensing. More importantly, discrimination and identification of them can be realized by using the sensors in an array way. Based upon the discoveries, a conceptual, two-sensor based detector is developed, and non-contact detection of the drugs is realized.

Constructing polycyclic aromatics-based highly emissive fluorophores with good solubility, tunable aggregated structures and properties is of great importance for film fabrication, solution processing and relevant functionality studies. Herein, we describe a general strategy to endow conventional organic fluorophores with enhanced solubility and modulated fluorescent properties via the incorporation into coordination-driven self-assembled metallacycles. A widely used fluorophore, pyrene, was decorated with two pyridyl groups to yield functionalized pyrene (4). Mixing 4 with three aromatic dicarboxylates with different lengths and a 90° Pt(II) metal acceptor in a 2:2:4 stoichiometric ratio resulted in the formation of three metallacycles (1, 2, and 3). The metallacycles display good solubility in polar organic solvents, highly aggregation-dependent fluorescence, and size-dependent emissions at higher concentrations. Moreover, metallacycle 2based, silica-gel supported film as fabricated is not only more emissive than the ligand, 4-based one, but also displays much improved sensing properties for amines in the vapor state as demonstrated by significantly increased response speed and decreased recovery time. The enhanced solubility, unique fluorescence behavior and multi-factor modulation character show that coordination-driven self-assembly can be utilized for the development of new fluorophores through simple modification of conventional fluorophores. The fluorophores synthesized this way possess not only complex topological structures but also good modularity and tunability in *

Poor processability of fullerenes is a major remaining drawback for them to be studied monomolecularly and to find real-life applications. One of the strategies to tackle this problem is to encapsulate them within a host, which is however quite often, accompanied by significant alteration of their physical/chemical properties as encountered in chemical modification. To minimize the effect, an electron-deficient entities-based, dissolvable, and fluorescence active supramolecular host was designed and constructed via coordination-driven self-assembly of o-tetrapyridyl perylene bisimide (PBI) with cis-(PEt3)2Pt­(OTf)2. The trigonal prism 1 possesses a trigonal-prismatic inner cavity with 14.7 Å as the diameter of its inscribed circle. Host–guest chemistry investigations revealed that both C60 and C70 could be quantitatively encapsulated by the host in a 1:1 ratio. Further studies demonstrated that the produced host–guest complex 1⊃C 70 is significantly more stable than 1⊃C 60 , allowing complete transformation of the latter to the former and separation of C70 from its mixture with C60. The fullerenes in the inclusion state could rotate freely within the cavity. Electrochemistry and spectroscopy studies disclosed that the encapsulation of the guests shows little effect upon the reduction of the host and its fluorescence properties. Thus, “like dissolves like” is believed to be the main driving force for the formation of the host–guest complexes. Moreover, the host and host–guest complexes can be fabricated into monomolecular membranes using the conventional Langmuir–Blodgett technique. We propose that these unique host–guest complexes could be used as model ensembles for further studies of the physical/chemical properties of fullerenes in both single molecular and 2D membrane states. In addition, their reversible four-electron reduction property may allow them to find applications in photo/electrocatalysis, organic electronics, etc.

Designing novel fluorophores with nonplanar structure and environmental sensitivity is of great significance for the development of high‐performance film‐based fluorescent sensors. Herein, a unique pentiptycene (P) and perylene bisimide (PBI)‐contained fluorescent dyad (P‐PBI‐P) displaying a switchable and tunable charge separated state is reported. It is demonstrated that this symmetrical and dumbbell‐like molecular dyad shows a greater extent of photoinduced intramolecular electron transfer than the asymmetrical dyad, P‐PBI. In addition, the charge separated state (P+‐PBI−‐P/P‐PBI−‐P+) of the fluorophore is super susceptive to solvent polarity, allowing sensitive detection of water content in organic liquids. Based on the finding, two P‐PBI‐P‐based fluorescent humidity sensors are fabricated, and they both show linear responses to air humidity within a range of at least 6.3% to 100% (relative humidity, RH). The response time is less than a few seconds, and the recovery time less than 1 min. Importantly, almost no hysteresis is found during a cyclic humidification and dehumidification test within the whole RH range studied. The superior performance of the humidity sensors based on the modulation of the charge separated state of a fluorophore constitutes an effective way for designing high‐performance film‐based fluorescent sensors.

Two simple, eco-friendly and efficient phase-selective gelators were developed for instant (<45 s) gelation of oil (either commercial fuels or pure organic liquids) from an oil-water mixture at room temperature to combat marine oil spills.