摘要：正在开发的新一代人工智能设备要求微型化和更高的工作功率，这就导致了更高的热通量密度，从而带来了潜在的火灾危险。目前的火灾报警传感器通常使用导电材料，而这些材料与短路触发火灾灾难所需的表面绝缘材料不兼容。本文，华中科技大学龙湖 研究员团队在《J. Mater.

1成果简介

正在开发的新一代人工智能设备要求微型化和更高的工作功率，这就导致了更高的热通量密度，从而带来了潜在的火灾危险。目前的火灾报警传感器通常使用导电材料，而这些材料与短路触发火灾灾难所需的表面绝缘材料不兼容。本文，华中科技大学龙湖 研究员团队在《J. Mater. Chem. C》期刊发表名为“LEGO®-inspired assembly strategy for fabricating BN-CNT-BN multilayer Kevlar-based composites as high-performance temperature sensors and fire alarms”的论文，研究提出了一种新的概念和制造方法，用于制造具有电绝缘表层的耐用且反应快速的火灾报警器。

最初，我们通过创建一种多层结构将火灾报警器的传感和防火功能分离开来，在这种结构中，导电热敏层被两个防火层夹在中间。传感器的制造采用了一种独特的乐高®组装策略，即创建一个纳米桥，将防火层包裹在热敏层上。该传感器具有超快的响应时间和恢复时间，分别仅为113.54 毫秒和 111.96 毫秒，而且在多次循环后仍具有很高的稳定性和耐用性。此外，表面的 BN-ANF 层还能保护内部的热敏层，使其与氧气隔绝，抑制碳纳米管的分解，从而使传感器能够用作火灾报警器。这种防火机制还用于提高焦耳加热膜在模拟短路条件下的防火安全性。这种新的设计理念和制造策略提高了复合薄膜的防火安全性，为开发高性能柔性传感器提供了新的灵感。

2图文导读

图1、 Schematic illustration of the LEGO®-inspired fire alarm assembly process.

图2、Characterization of the sandwiched composite film: (a) cross-sectional scheme of the sandwiched composite film. (b) Cross-sectional SEM image of the sandwiched composite film. (c) The interface between the protective BN-ANF layer and base ANF layer. (d) The interface between the protective BN-ANF layer and CNT layer. (e) The interface between the protective base ANF layer and CNT layer. (f) The Raman spectra of each functional layer.

图3、Temperature sensing performance of the sandwiched composite film. (a) The temperature of thermally sensitive layer corresponding to the temperature of the surface protective layer. (b) Dynamic test of the temperature sensor by exposure to a surface temperature increased stepwise. (c) Cyclical durability test of sensor via repeated cold-plate and hot-plate exposure. (d) Experimental and linear fitting of the relationship between surface temperatures and electrical response. (e) and (f) Response and recovery time evaluation at the beginning and the end of the cyclical durability test. (g) The response time and corresponding temperature variation compared with other reported works.

图4、Flame retardant ability of the sandwiched composite film and its application as a fire alarm. (a) and (b) The burning tests of the sample with and without a surface BN-ANF protective layer. (c) Thermal gravimetric analysis of the sample with and without a surface BN-ANF protective layer. (d) The heat release rate during the combustion of the sample with and without a surface BN-ANF protective layer. (e) The total heat release during the combustion of the sample with and without a surface BN-ANF protective layer. (f) The variation of electrical resistance during the combustion of the sample with and without a surface BN-ANF protective layer. (g) and (h) Fire alarm application of the sample with a BN-ANF protective layer. (i) Duration test of the fire alarm.

图5、 Joule heating performance of the sandwiched composite film: (a) temperature of the sandwiched composite film under stepwise-increased power input. (b) Experimental and linear fitting of the relationship between surface temperature and input voltage. (c) Temperature stability of the sandwiched composite film at a constant voltage of 8 V analyzed using surface IR for 600 s. (d) Cyclical durability test with an input voltage of 3 V. (e) The resistance stability of the conductive layer before and after the assembly of the protective layer. (f) and (g) Fire safety test of the heater with a bare surface and a BN surface protective layer under the same input voltage.

3小结

受乐高玩具组装过程的启发，我们提出了一种组装具有独特功能的复合薄膜的新型制造方法。利用受乐高®启发的纳米桥组装策略，在复合薄膜上沉积导电层，并在两侧封装BN-ANF层。与之前报道的传感器相比，这种复合薄膜显示出卓越的温度传感能力，具有出色的稳定性和超快的响应时间。此外，BN-ANF 保护层还能减轻CNTs导电层的降解，从而增强阻燃性，使其成为一种前景广阔的火灾报警传感器。为火灾报警应用设计的专用电路实现了小于 3 秒的快速响应时间和超过 1200 秒的持续耐用性。利用所发现的防火机制，复合薄膜在相对较低的工作电压下表现出卓越的焦耳加热性能，并具有出色的稳定性和耐用性。BN-ANF 表层在短路条件下表现出有效的防火性能。这项研究为设计和制造火灾报警器开辟了新的途径，为增强消防安全应用提供了巨大潜力。

文献：

来源：材料分析与应用

来源：石墨烯联盟