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Phosphorescent materials have received considerable attention in organic solar cells (OSCs) due to their long emission lifetime and inhibited geminate recombination. Motivated by its particular photophysical property, herein, the spatially addressable bis(2‐benzo[b]thiophen‐2‐ylpyridine)(acetylacetonate)iridium(III) (Ir(bt)2(acac))/polystyrene‐b‐poly(4‐vinylpyridine) (PS‐b‐P4VP) as a photoactive floating‐gate is first demonstrated to explore the application of phosphorescent material on the photo‐responsive characteristics of photomemory and artificial photonic synapse. By manipulating the interfacial area between Ir(bt)2(acac)/PS‐b‐P4VP and active channel by a solvent annealing process, an ON/OFF current ratio of 103 and a low programming time of 700 ms can be achieved. The current study addresses the exciton lifetime of photoactive material functions in photomemory and highlights the interfacial area between photoactive materials and charge‐carrier transporting materials in reducing photo‐programming time. [ABSTRACT FROM AUTHOR]

Ultrasmall silica‐based nanoparticles (SNPs) are attractive for application in many fields, but existing synthetic approaches show limited control over the size and morphology of these SNPs. This study describes a general single copolymer chain‐mediated strategy for the scalable synthesis of highly monodispersed symmetric and asymmetric SNPs with sub‐50 nm diameter. Random copolymers of poly(acrylic acid‐r‐styrene) intramolecularly collapse into ultrasmall single‐chain nanoparticles and serve as seeds to template the hydrolysis of silica precursors to produce uniform SNPs. It is shown in experiments and simulations that the composition and random architecture of the copolymers are crucial to the formation of ultrasmall seeds and the uniform deposition of silica. Furthermore, tailoring the architecture of copolymers can be used to produce ultrasmall asymmetric Janus‐like and dumbbell‐like SNPs with well‐defined polymer and silica domains. This study paves a new route to the scalable production of ultrasmall SNPs with tailored morphologies. [ABSTRACT FROM AUTHOR]

Solution‐processable organic–inorganic hybrid perovskite materials have been applied to a variety of optoelectronic devices due to its long exciton lifetime and small binding energy. It has emerged as promising front‐runners for next‐generation non‐volatile flash photomemory devices. However, the effect of crystal orientation of perovskite on the performance of photomemory still has not fully developed. Herein, non‐volatile flash photomemory with quasi‐2D perovskite/polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO) as photoactive floating‐gate and p‐type semiconductor poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) as the chare‐transporting layer is successfully demonstrated. By adding phenylethylammonium bromide (PEABr) in formamidinium lead bromide perovskite (FAPbBr3), the crystal orientation of quasi‐2D perovskite is highly improved, which results in raised charge transfer efficiency from 76% to 90% compared to the pure FAPbBr3. Furthermore, ON/OFF current ratio of 104, low photo‐programming time of 5 ms under light intensity of 0.85 mW cm−2, charge transfer rate of 0.063 ns−1, and data storage capacity of over 7 bits (128 levels) in one cell can be achieved. In addition, the correlation between photo‐responsive current and photoluminescence (PL) is first examined by in operando PL measurement, which provides a new platform to explore the charge transfer process in photomemory. [ABSTRACT FROM AUTHOR]