Lei Wang, Zhonglei Ma, Yali Zhang, Hua Qiu*, Kunpeng Ruan and Junwei Gu*. Mechanically Strong and Folding-Endurance Ti3C2Tx MXene/PBO Nanofibers Films for Efficient EMI Shielding and Thermal Management. Carbon Energy, 2022, 10.1002/cey2.174. 2021即時因子19.741.（中國科技期刊卓越行動計劃高起點新刊）
https://doi.org/10.1002/cey2.174
Abstract
Electromagnetic interference (EMI) shielding materials with excellent flexibility & mechanical properties, and outstanding thermal conductivity have become a research hotspot in functional composites. In this work, the“sol-gel-film conversion technique” is used to assemble polyetherimide functionalized Ti3C2Tx nanosheets (f-Ti3C2Tx) with poly(p-phenylene-2,6-benzobisoxazole) (PBO) nanofibers (PNFs), followed by dialysis and vacuum drying to prepare the f-Ti3C2Tx/PNFs films with lamellar structures. When the loadings of f-Ti3C2Tx is 70 wt%, the f-Ti3C2Tx/PNFs film presents the optimal comprehensive properties, with EMI shielding effectiveness (SE) of 35 dB and specific SE/thickness ((SSE, SE/density)/t) of 8211 dB·cm2/g, tensile strength of 125.1 MPa, in-plane thermal conductivity coefficient of 5.82 W/(m·K), and electrical conductivity of 1943 S/m. After repeated folding for 10000 cycles, the EMI SE and tensile strength of f-Ti3C2Tx/PNFs films still maintain at 33.4 dB and 116.1 MPa, respectively. Additionally, f-Ti3C2Tx/PNFs film also shows excellent thermal stability, flame retardancy, and structural stability. It would provide a novel method for the design and fabrication of multifunctional composite films, and greatly expand the applications of MXene and PNFs-based composites in the fields of EMI shielding and thermal management.
兼具柔性、超高力學強度和優異導熱性能的電磁屏蔽材料已成為功能復合材料領域的研究熱點和重要組成部分。本文通過“溶膠-凝膠-薄膜轉化技術”將聚醚酰亞胺功能化的Ti3C2Tx納米片（f-Ti3C2Tx）與poly(p-phenylene-2,6-benzobisoxazole，PEI)納米纖維（PNFs）復合制備f-Ti3C2Tx/PNFs有機凝膠，再通過溶劑置換并真空干燥制得層狀結構的f-Ti3C2Tx/PNFs薄膜。當f-Ti3C2Tx納米片用量為70 wt%時，f-Ti3C2Tx/PNFs薄膜具有最佳的綜合性能，其屏蔽效能（EMI SE）和比屏蔽效能/厚度（（SSE，SE/密度）/t）分別為35 dB和8211 dB·cm2/g，拉伸強度、面內導熱系數（λ//）和電導率（σ）分別為125.1 MPa、5.82 W/(m·K)和1943 S/m；折疊10000多次后其EMI SE和拉伸強度仍維持在33 dB和116.1 MPa。f-Ti3C2Tx/PNFs薄膜同時具有卓越的熱穩定性（800oC退火后的質量損失僅為18.7 wt%）、優異的阻燃性能（酒精燈灼燒下無任何火焰）和結構穩定性（水中超聲1 hr或浸泡72 hrs后無任何結構破壞）。這種具有優異λ、超高力學性能、卓越屏蔽性能、出色阻燃性能和耐疲勞性能的f-Ti3C2Tx/PNFs薄膜將為多功能復合薄膜的設計研發提供一定的借鑒意義，并極大地拓展MXene基納米復合材料以及PNFs基納米復合材料在電磁屏蔽和熱管理領域中的應用。