The fabrication of high‐performance nonvolatile organic field effect transistor (OFET) memory devices is reported using a series of pyrene‐fused pyrazaacene (PPA) and 9,10‐imide‐pyrene‐fused pyrazaacene (IPPA) derivatives as n‐type doping components. The obtained memory devices exhibit stable switching behaviors (>100 times) and good retention properties (>104 s). Devices based on chlorinated IPPA (IPPA‐Cl) show the largest memory window of 40.8 V, with a trapping charge density of 2.66 × 1012 cm−2 and on/off ratio higher than 106. Our investigation reveals that low‐lying lowest unoccupied molecular orbital energy levels and small dipole moment are key parameters for achieving high memory performance. This work provides a general guideline for the design of n‐type organic semiconductors as highly efficient doping materials for organic memory devices.

The flammability of the biodegradable plastic PLA limits its application in industrial fields with high flame-retardant requirements. This paper provides a novel strategy for constructing refractory and thermostable PLA composites using layered double hydroxides (LDHs) chemically modified with ammonium polyphosphate (APP). XRD, FT-IR, SEM-EDS, and TEM confirm that the goal of LDHs has been successfully prepared. The thermal stability and combustion behavior of PLA composites were evaluated by the thermogravimetric analysis (TGA) and cone calorimetry tests (CCT). The crystallization behavior and tensile performances were also examined. The results showed that the incorporation of 15 wt% MgAlY-APP-LDHs practically makes the PLA composites reach the UL-94 V-0 grade. There were 43% and 20% reduction in the PHRR and THR of PLA/15APP-LDHs respectively due to the catalytic effect of Y elements and barrier effects of LDHs, which was a major performance against fire hazards. Furthermore, the increase in crystallinity and the decrease in mechanical strength of PLA composites are attributed to the nucleation of LDHs. In short, this research introduces the production of multifunctional PLA composites through APP intercalation of LDHs, which are deemed as prospective candidates for the next generation of sustainable plastics products.

Comprehensive SummarySinglet fission (SF) has potential applications in high‐efficiency photo‐energy harvesting applications, but its practical application is hindered by the limited number of materials. In this work, we explored the bay aromatic substitution strategy for the design of new perylenediimide (PDI) based SF materials. A series of PDI derivatives with biphenyl or naphthalene units substituted at the bay positions were designed and synthesized to investigate the effects of aromatic substitutes on their photodynamic behaviours. The bay substitutions do not shift the energy level of the PDI core significantly but give rise to different intermolecular coupling strengths in the thin films and affect the intermolecular SF efficiency. Femtosecond transient absorption (fsTA) spectroscopy reveals that appropriate spacing configuration from the bay aromatic substitution groups enhances the SF yields by promoting the interaction of neighbouring PDI cores. Triplet exciton yields of up to 183% have been obtained from these new PDI derivatives, making them potential candidates in future SF‐based optoelectronics.

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