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Boron nitride (BN) has garnered significant attention for its potential in developing thermally conductive materials owing to its inherent insulating properties and high thermal conductivity. However, achieving high thermal conductivity in bulk materials or 3D structures constructed by BN sheets has remained challenging. In this study, we present a novel approach to design a high‐quality BN fiber using xanthan gum (XG) as a skeleton, aiming to facilitate heat dissipation in integrated circuits. The resulting thermally conductive film, with orderly and compactly arranged BN sheets in the XG skeleton, exhibits a remarkable in‐plane thermal conductivity of 8.26 Wm−1 K−1 and an out‐of‐plane thermal conductivity of 1.35 Wm−1 K−1. This film efficiently enables fast heat dissipation for LED chips and thermoelectric generators. Finite element simulation further supports the efficient heat transfer capacity of the BN fiber films. Highlights: A high‐quality BN fiber was prepared by a facile approach.The BN fiber film exhibited high thermal conductivity.This film enables fast heat dissipation in practical applications. [ABSTRACT FROM AUTHOR]

In recent years, organic–inorganic hybrid halide perovskite materials have been found to have low thermal conductivity and a large Seebeck effect, giving them great potential for thermoelectric applications. More stable single crystals make this possible. In this work, high‐quality MAPbI3 single crystals are prepared using a modified solvent engineering method, and their trap density is as low as 2.5 × 109 cm−3. It is noticed that the reaction between the crystal a metal electrode causes different degrees of doping effect along the vertical direction, leading to an increase in the intrinsic P‐type with Au metal, and forming N‐type semiconductor characteristics with Ag metal. A high Seebeck voltage thermoelectric module is obtained by combining the perovskite single crystal with different conductive characteristics. After device optimization, the thermoelectric potential of the champion module reaches a high voltage of 337 mV at 115 °C, the maximum output power with load reaches about 30 nW, and the theoretical maximum power reaches 65 nW. It is hoped that this research can promote the development of low thermal conductivity perovskite materials in the thermoelectric field. [ABSTRACT FROM AUTHOR]

A booming demand for wearable electronic devices urges the development of multifunctional smart fabrics. However, it is still facing a challenge to fabricate multifunctional smart fabrics with satisfactory mechanical property, excellent Joule heating performance, highly efficient photothermal conversion, outstanding electromagnetic shielding effectiveness, and superior anti-bacterial capability. Here, a MoSe 2 @MXene heterostructure-based multifunctional cellulose fabric is fabricated by depositing MXene nanosheets onto cellulose fabric followed by a facile hydrothermal method to grow MoSe 2 nanoflakes on MXene layers. A low-voltage Joule heating therapy platform with rapid Joule heating response (up to 230 °C in 25 s at a supplied voltage of 4 V) and stable performance under repeated bending cycles (up to 1000 cycles) is realized. Besides, the multifunctional fabric also exhibits excellent photothermal performance (up to 130 °C upon irradiation for 25 s with a light intensity of 400 mW cm -2 ), outstanding electromagnetic interference shielding effectiveness (37 dB), and excellent antibacterial performances (>90% anti-bacterial rate toward Escherichia coli, Bacillus subtilis, and Staphylococcus aureus). This work offers an efficient avenue to fabricate multifunctional wearable thermal therapy devices for mobile healthcare and personal thermal management., (© 2022 Wiley-VCH GmbH.)