Tin perovskite solar cells (TPSCs) are rising as the most promising candidates for lead-free PSCs. However, the randomly crystallized tin halide perovskite with high concentration of defects is still the...

Rigid fused perylene diimide (PDI) dimers bridged with heterocycles exhibit superior photovoltaic performance compared to their unfused semiflexible analogues. Changing the chalcogen atoms in the aromatic bridges gradually increases the twist angles between the two PDI planes, leading to a varied morphology in which the one bridged by thiophene achieves a balance and shows the best efficiency of 6.72%.

Solution-processable organic-inorganic hybrid perovskite materials with a wealth of exotic semiconducting properties have appeared as the promising front-runners for next-generation electronic devices. Further, regarding its well photoresponsibility, various perovskite-based photosensing devices are prosperously developed in recent years. However, most exploited devices to date only transiently transduce the optical signals into electrical circuits while under illumination, which necessitates using additional converters to further store the output signals for recording the occurrence of light stimulation. Herein, a nonvolatile perovskite-based floating-gate photomemory with a multilevel memory behavior is demonstrated, for which a floating gate comprising a polymer matrix impregnated with perovskite nanoparticles is employed. Owing to the well photoresponsibility introduced by the embedded nanoparticles, the device is enabled to access multiple wavelength response and the functionalities of recording power/time-dependent illumination under no vertical electrical field. Intriguingly, a nonvolatility of photorecording exceeding three months with a high On/Off current ratio over 10 can be achieved.

A molecular nano‐floating gate (NFG) of pentacene‐based transistor memory devices is developed using conjugated polymer nanoparticles (CPN) as the discrete trapping sites embedded in an insulating polymer, poly (methacrylic acid) (PMAA). The nanoparticles of polyfluorene (PF) and poly(fluorene‐alt‐benzo[2,1,3]thiadiazole (PFBT) with average diameters of around 50–70 nm are used as charge‐trapping sites, while hydrophilic PMAA serves as a matrix and a tunneling layer. By inserting PF nanoparticles as the floating gate, the transistor memory device reveals a controllable threshold voltage shift, indicating effectively electron‐trapping by the PF CPN. The electron‐storage capability can be further improved using the PFBT‐based NFG since their lower unoccupied molecular orbital level is beneficial for stabilization of the trapped charges, leading a large memory window (35 V), retention time longer than 104 s with a high ON/OFF ratio of >104. In addition, the memory device performance using conjugated polymer nanoparticle NFG is much higher than that of the corresponding polymer blend thin films of PF/polystyrene. It suggests that the discrete polymer nanoparticles can be effectively covered by the tunneling layer, PMAA, to achieve the superior memory characteristics.

b S Supporting Information ' INTRODUCTION Regioregular poly(3-alkylthiophenes) (P3HT) have attracted extensive scientific interest due to their superior charge-transporting characteristics and favorable processability for optoelectronic device applications, such as photovoltaic cells (PV) 1À4 and organic field-effect transistor (OFET). 5À9 Aligned one-dimensional (1D) structure with nanometer-sized confinement would significantly enhance the orientation of P3HT crystals, which is more favorable for its anisotropic charge transport than the unaligned 1D structure. The charge-carrier mobility of P3HT OFET could be manipulated over a wide range of 4 Â 10 À4 to 3 Â 10 À2 cm 2 /V 3 s through different nanostructure or orientation on crystal domains, such as nanofibers. 10À15 P3HT nanofibers were generally produced via solution selfassembly 11,12 or electrospinning (ES). 13À15 We are particularly interested in producing polymer nanofibers through the ES process because it has the advantages of low cost, flexible morphology tuning, and high-throughput continuous production. 16À20 The strong stretching force and the geometrical confinement associated with the ES process could induce the orientation of polymer chains along the long axis of fiber, 21À23 whose photoelectronic properties were different from that in the spin-coated films. 24À31 In addition, ES aligned nanofibers were easily prepared from several approaches, 32À38 including a scanning tip, 32 a drum rotating at a high speed, 33 a rotating wheel-like bobbin, 34 collector/electrode modification, 22,35,36 and magnetic field-assistance. 37 Liu et al. prepared single P3HT ES nanofiber-based OFET with the mobility as high as 0.03 cm 2 /V 3 s. 14 However, droplets and beaded P3HT nanofibers were occasionally formed due to the rapid evaporation of the solvent and low polymer solubility. Recently, Lee et al. used the coaxial setup to produce continuous and uniform P3HT ES nanofibers with the carrier mobility of 0.017 cm 2 /V 3 s, by continuously providing solvent in the shell to prevent the phase separation of P3HT from the solution at the end