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.

New strategies are in high demand for fast, sensitive, selective, on‐site and real‐time detection of the important but challenging alkane vapors owing to their opto‐electronic inertness. Herein, we report, for the first time, a high‐performance fluorescent film sensor (FFS) for the alkanes with a rationally designed through‐space charge transfer (TSCT) molecule as the sensing fluorophore. Steady‐state fluorescence, femto‐second transient absorption spectroscopy and theoretical studies revealed continuous TSCT dynamics in the excited U‐shaped molecule with increasing medium polarity. Furthermore, the interlocked, face‐to‐face alignment between the donor and acceptor favors mass transport of the analyte molecules in the film state. As anticipated, the compound‐based FFS showed an experimental detection limit of ≈10 ppm for n‐pentane, less than 5 s for a full detection, negligible interference and super‐stability, revealing the effectiveness of the design strategy. Notably, the sensor is small (≈3.7 cm3), power‐saving, and workable at room temperature.

Smart luminescent materials with tangible and reversible responses to external stimuli have gained popularity for multiple applications. However, impracticable stimuli and less adaptability render them unfit for real‐life applications. Here, a proton competitive binding‐based molecular system is reported, which demonstrates, both in solution and solid state, remarkable responses toward light illumination and temperature variation. Small change in solvent composition could result in remarkable variation in measurable temperature range at least from −80 to 60 °C. Combination of light illumination and temperature change enables multilevel anti‐counterfeiting, as well as construction of easy‐to‐use and high‐resolution liquid thermometers. The key components in the concerned molecular system are a newly designed fluorophore, NI‐CBN, a four‐coordinated boron derivative of naphthalimide (NI), and an organic fluoride salt that is tetrabutylammonium fluoride (TBAF). Reaction between NI‐CBN and TBAF yields a dynamic fluorophore, NI‐CBN‐F, which shows remarkable color change to the stimuli via proton migration between the imine group in NI‐CBN and the fluoride anion of the salt. Such responses enable the aforementioned advanced anti‐counterfeiting and visible temperature monitoring.

Iridium complexes have been widely applied as molecular sensors because of their rich photophysical properties, including large Stokes shifts, long emission lifetimes, environment-sensitive emissions, and high luminescent quantum yields. In...

Integrating multiple photosensitive properties into an "all-in-one" photosensitizer (PS) shows great promise for the treatment of cancers owing to synergistic effect among them. However, the development of such PSs, especially those that need a single laser source, remains a challenge. Herein, we report an orchestration of electron donors and acceptors in a propeller-like pentad, PBI-4Cz, where four carbazole (Cz) units are covalently linked to the ortho-positions of the perylene bisimide (PBI) core. Strong intramolecular donor-acceptor interaction significantly quenches the luminescence and largely extends the absorption spectra to near-infrared region. Excited-state dynamics investigated via femto-and nano-second transient absorption spectroscopy revealed exclusive charge separation of the PBI-4Cz within initial 0.5 ps when photoexcited regardless of which intermediate is involved. Energy dissipation of the resulting charge-separated state (PBI •− -4Cz•+ ) is subjected to the toggle between intersystem-crossing toward excited triplet states and charge recombination toward ground states. Relative importance of the two pathways can be tuned by micro-environmental polarity, which endows PBI-4Cz remarkable performances of singlet-oxygen generation (>90.0%) in toluene and photothermal conversion (~28.6%) in DMSO. Harnessing intrinsic photostability and excited-state processes of heavy-atom-free PBI derivatives not only holds a promise for multifunctional phototheranostics, but also provides a prototype for designing high-performance PSs with tunable photoconversion pathways.