Organic molecular semiconductors are key components for a new generation of low cost, flexible, and large area electronic devices. In particular, ambipolar semiconductors endowed with electroluminescent properties have the potential to enable a photonic field-effect technology platform, whose key building blocks are the emerging organic light-emitting transistor (OLET) devices. To this aim, the design of innovative molecular configurations combining effective electrical and optical properties in the solid state is highly desirable. Here, we investigate the effect of the insertion of a thieno(bis)imide (TBI) moiety as end group in highly performing unipolar oligothiophene semiconductors on the packing, electrical, and optoelectronic properties of the resulting materials. We show that, regardless of the HOMO–LUMO energy, orbital distribution, and molecular packing pattern, a TBI end moiety switches unipolar and nonemissive oligothiophene semiconductors to ambipolar and electroluminescent materials. Remarkably, the newly developed materials enabled the fabrication of single layer molecular ambipolar OLETs with optical power comparable to that of the equivalent polymeric single layer devices.

Despite the variety of functional properties of molecular materials, which make them of interest for a number of technologies, their tendency to form inhomogeneous aggregates in thin films and to self-organize in polymorphs are considered drawbacks for practical applications. Here, we report on the use of polymorphic molecular fluorescent thin films as time temperature integrators, a class of devices that monitor the thermal history of a product. The device is fabricated by patterning the fluorescent model compound thieno(bis)imide-oligothiophene. The fluorescence colour of the pattern changes as a consequence of an irreversible phase variation driven by temperature, and reveals the temperature at which the pattern was exposed. The experimental results are quantitatively analysed in the range 20–200°C and interpreted considering a polymorph recrystallization in the thin film. Noteworthy, the reported method is of general validity and can be extended to every compound featuring irreversible temperature-dependent change of fluorescence.

This work explored polysulfone (PS)-graphene oxide (GO) based porous membranes (PS-GO) as adsorbent of seven selected organic contaminants of emerging concern (EOCs) including pharmaceuticals, personal care products, a dye and a surfactant from water. PS-GO was prepared by phase inversion method starting from a PS and GO (5% w/w mixture). The porous PS-GO membranes showed asymmetric and highly porous micrometer sized pores on membrane top (diameter ≈20 μm) and bottom (diameter ≈ 2-5 μm) surfaces and tens of microns length finger like pores in the section. Nanomechanical mapping reveals patches of a stiffer material with Young modules comprised in the range 15-25 GPa, not present in PS pure membranes that are compatible with the presence of GO flakes on the membrane surfaces. PS-GO was immersed in EOCs spiked tap water and the adsorbance efficiency in time and at different pH evaluated by HPLC analyisis. Ofloxacin (OFLOX), Benzophenone-3 (BP-3), rhodamine b (Rh), DCF and triton X-100 (TRX) were removed with efficiency higher than 90% after 4 hours treatments. Regeneration of PS-GO and reuse possibilities were demonstrated by washing with ethanol. The adsorption efficiency toward were Moreover, PS-GO outperformed a commercial granular activated carbon (GAC) at low contact times and compared well at longer contact time for OFLOX, Rh, BP-3 and TRX suggesting the suitability of the newly introduced material for drinking water treatment.

We report a successful chemical design strategy based on the even-odd alkyl end tailoring, which allows us to promote and control conformational polymorphism in single crystal and thin deposits of thienoimide-based molecular semiconductors (Cx-NT4N).