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Highly thermal conductive polymer composites with minimized content of fillers are desirable for handling the issue in thermal management in modern electronics. However, the difficulty of filler dispersion restricts the heat dissipation performance of thermoplastic composites and the intermolecular interaction is another crucial factor in this problem. In the present study, the hydrogen bond was used to regulate the formation of the three-dimensional boron nitride (3D BN) interconnected network to act as a high thermal conductive network in thermoplastic polyamide-imide (PAI) materials. The prepared electrical insulated PAI/3D-BN composites have a thermal conductivity (TC) of 1.17 W·m·K at a low BN loading of 4 wt %/2 vol % and exhibit a thermal conductivity enhancement of 409%. We attribute the increased TC to the construction of 3D BN interconnected network and the hydrogen bond regulated between hydroxylated BN and polyvinyl alcohol, in which an effective thermal conductive network is constructed. This study provides a guided hydrogen bond strategy for thermally conductive polymer composites with good mechanical and electrical insulation properties in thermal management and other applications.

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Bismuth triiodide, BiI, is one of the promising 2D layered materials from the family of metal halides. The unique electronic structure and properties make it an attractive material for the room-temperature gamma/X-ray detectors, high-efficiency photovoltaic absorbers, and Bi-based organic-inorganic hybrid perovskites. Other possibilities including optoelectronic devices and optical circuits are envisioned but rarely experimentally confirmed yet. Here, we report the synthesis of vertical 2D BiI nanoplates using the physical vapor deposition mechanism. The obtained products were found easy to be separated and transferred to other substrates. Photodetectors employing such 2D nanoplates on polyethylene terephthalate substrate are demonstrated to be quite sensitive to red light (635 nm) with good responsivity (2.8 A W), fast stable photoresponse (3/9 ms for raise/decay times), and remarkable specific detectivity (1.2 × 10 jones), which attest to high comparability of the assembled components with many latest 2D nanostructured light sensors. In addition, such photodetectors exhibit outstanding mechanical stability and durability under different bending strains within the theoretically affordable levels, suggesting a variety of potential applications of 2D BiI for flexible devices.

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Polymer materials with high thermal conductivities play an important role in the development of next-generation electronics. In this work, high thermally conductive nanofibrillated cellulose (NFC) hybrid films based on nanodiamonds (NDs) and graphene sheets (GSs) were prepared by a facile vacuum-filtration self-assembly process. Inspired by the structure of nacre, zero-dimensional NDs, two-dimensional GSs, and one-dimensional NFC were used to build hierarchical structures, which lead to excellent mechanical properties of the hybrid films. More importantly, an efficient thermally conductive pathway, involving NDs and GSs, endows the hybrid films with a much higher in-plane thermal conductivity. At a filler content of 10 wt %, the in-plane thermal conductivity of the f-C/ND/G hybrid film could reach 14.35 W·m–1·K–1, which is at a high level compared with other published studies. This hybrid film exhibits significant thermal conductivity combined with excellent mechanical properties that can be applied to portable electronic equipment as a lateral heat spreader.

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