In spite of extensive studies conducted on carbon nanotubes and silicate layers for their polymer-based nanocomposites, the rise of graphene now provides a more promising candidate due to its exceptionally high mechanical performance and electrical and thermal conductivities. The present study developed a facile approach to fabricate epoxy-graphene nanocomposites by thermally expanding a commercial product followed by ultrasonication and solution-compounding with epoxy, and investigated their morphologies, mechanical properties, electrical conductivity and thermal mechanical behaviour. Graphene platelets (GnPs) of 3.57 AE 0.50 nm in thickness were created after the expanded product was dispersed in tetrahydrofuran using 60 min ultrasonication. Since epoxy resins cured by various hardeners are widely used in industries, we chose two common hardeners: polyoxypropylene (J230) and 4,4 0 -diaminodiphenylsulfone (DDS). DDS-cured nanocomposites showed a better dispersion and exfoliation of GnPs, a higher improvement (573%) in fracture energy release rate and a lower percolation threshold (0.612 vol%) for electrical conductivity, because DDS contains benzene groups which create p-p interactions with GnPs promoting a higher degree of dispersion and exfoliation of GnPs during curing. This research pointed out a potential trend where GnPs would replace carbon nanotubes and silicate layers for many applications of polymer nanocomposites.

Utilization of triplet excitons, which generally emit poorly, is always fundamental to realize highly efficient organic light-emitting diodes (LEDs). While triplet harvest and energy transfer via electron exchange between triplet donor and acceptor are fully understood in doped organic phosphorescence and delayed fluorescence systems, the utilization and energy transfer of triplet excitons in quasitwo-dimensional (quasi-2D) perovskite are still ambiguous. Here, we use an orangephosphorescence-emitting ultrathin organic layer to probe triplet behavior in the skyblue-emitting quasi-2D perovskite. The delicate white LED architecture enables a carefully tailored Dexter-like energy-transfer mode that largely harvests the triplet excitons in quasi-2D perovskite. Our white organic−inorganic LEDs achieve maximum forward-viewing external quantum efficiency of 8.6% and luminance over 15 000 cd m −2 , exhibiting a significant efficiency enhancement versus the corresponding sky-blue perovskite LED (4.6%). The efficient management of energy transfer between excitons in quasi-2D perovskite and Frenkel excitons in the organic layer opens the door to fully utilizing excitons for white organic−inorganic LEDs.

Snake venom is one of the most lethal saliva toxins in the world. It consists of more than 20 distinct compounds, mainly of which are proteins， peptides or polypeptides. Proteins are responsible for 90%-95% of snake venom’s dry weight and are capable of some biological uses. The venom facilitates digestion and immobilization of prey and can help the snake to resist threats as well. Snake bites can easily kill a human or any other animal species. There are multiple sorts of snake venom with different toxicity abilities, causing various physiological effects. While snake venom is considered as a highly risky toxin, it still can be used to benefit human beings. For example, in the biomedical area, specific snake venom can treat serval diseases and even has a cosmetic effect. This article will solve the question that how snake venom can be lethal and beneficial at the same time, and how it be used to contribute to biological resources.

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