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In this paper, Salen‐Ni basis polyphosphazene microsphere (Salen‐PZN‐Ni), boric acid (BA), and 3‐aminopropyltriethoxysilane (KH‐550) were used as raw materials to prepare a new flame retardant Salen‐PZN‐Ni@BA@KH‐550 by surface modification. The thermal and flame retardant properties of epoxy resin (EP) composites were studied. The introduction of Salen‐PZN‐Ni@BA@KH‐550 refined the thermal stability of EP composites, as well as the amount of carbon residue at 800°C. At 5 wt% of Salen‐PZN‐Ni@BA@KH‐550, the limiting oxygen index (LOI) of EP composites is increased from 25.4% to 30.5% and UL‐94 has been achieved with a V‐1 rating. Meanwhile, the mechanical properties of Salen‐PZN‐Ni@BA@KH‐550/EP composites were also improved. In addition, the good char formation ability of Salen‐PZN‐Ni@BA@KH‐550 caused the reduction of peak heat release rate, total heat release rate, maximum average heat release rate and total smoke generation of the EP composites. All these results indicate that Salen‐PZN‐Ni@BA@KH‐550/EP composites have a wider range of applications.

 

Abstract A fascinating photonic platform with a small device scale, fast operating speed, as well as low energy consumption is two-dimensional (2D) materials, thanks to their in-plane crystalline structures and out-of-plane quantum confinement. The key to further advancement in this research field is the ability to modify the optical properties of the 2D materials. The modifications typically come from the materials themselves, for example, altering their chemical compositions. This article reviews a comparably less explored but promising means, through engineering the photonic surroundings. Rather than modifying materials themselves, this means manipulates the dielectric and metallic environments, both uniform and nanostructured, that directly interact with the materials. For 2D materials that are only one or a few atoms thick, the interaction with the environment can be remarkably efficient. This review summarizes the three degrees of freedom of this interaction: weak coupling, strong coupling, and multifunctionality. In addition, it reviews a relatively timing concept of engineering that directly applied to the 2D materials by patterning. Benefiting from the burgeoning development of nanophotonics, the engineering of photonic environments provides a versatile and creative methodology of reshaping light–matter interaction in 2D materials. 

Graphene (Gr) has many unique properties including gapless band structure, ultrafast carrier dynamics, high carrier mobility, and flexibility, making it appealing for ultrafast, broadband, and flexible optoelectronics. To overcome its intrinsic limit of low absorption, hybrid structures are exploited to improve the device performance. Particularly, van der Waals heterostructures with different photosensitive materials and photonic structures are very effective for improving photodetection and modulation efficiency. With such hybrid structures, Gr hybrid photodetectors can operate from ultraviolet to terahertz, with significantly improvedR(up to 10⁹A W⁻¹) and bandwidth (up to 128 GHz). Furthermore, integration of Gr with silicon (Si) complementary metal‐oxide‐semiconductor (CMOS) circuits, the human body, and soft tissues is successfully demonstrated, opening promising opportunities for wearable sensors and biomedical electronics. Here, the recent progress in using Gr hybrid structures toward high‐performance photodetectors and integrated optoelectronic applications is reviewed.

 

Solvents are essential in synthesis, transfer, and device fabrication of 2D materials and their functionalized forms. Controllable tuning of the structure and properties of these materials using common solvents can pave new and exciting pathways to fabricate high‐performance devices. However, this is yet to be materialized as solvent effects on 2D materials are far from well understood. Using fluorine functionalized chemical vapor deposited graphene (FG) as an example, and in contrast to traditional “hard‐patterning” method of plasma etching, the authors demonstrate a solvent‐based “soft‐patterning” strategy to enable its selective defluorination for the fabrication of graphene‐FG lateral heterostructures with resolution down to 50 nm. In this strategy, the oxygen plasma etching process of patterning after graphene transfer is avoided and high quality surfaces are preserved through a physically continuous atomically thin sheet, which is critical for high performance photodetection, especially in the high‐speed domain. The fabricated lateral graphene heterostructures are further employed to demonstrate a high speed metal–semiconductor–metal photodetector (<10 ns response time), with a broadband response from deep‐UV (200 nm) to near‐infrared (1100 nm) range. Thanks to the high quality surface with much less defects due to the “soft‐patterning” strategy, the authors achieve a high deep‐UV region photoresponsivity as well as the ultrafast time response. The strategy offers a unique and scalable method to realize continuous 2D lateral heterostructures and underscores the significance of inspiring future designs for high speed optoelectronic devices.