Shuai Zhang,Yin Zhang,Yanping Huang,Bingqun Lin,Shengjie Ling,Changtong Mei,Mingzhu Pan
With the acceleration of urbanization, energy-efficient, comfortable, and lightweight materials have been growing widely used. An ideal real-time monitoring strategy integrated with prominent fire sensing capability, flame retardancy, and embedded in communication network Internet of Things (IoT) remains a huge concern. Here, we develop a sensitive and durable fire alarm intelligent coating strategy based on a metal-insulator transitional Ti 3 O 5 via a layer-by-layer assembly (LBL). We elucidate the atomic structure, electronic band, and orbital structure of Ti 3 O 5 correlated from the charge-ordered β-phase (electrical insulation state) to valence-delocalized of α-phase (electrical conduction state) during switchable temperature by density functional theory (DFT) calculations. Accordingly, a thermally activated electron jump among the localized states facilitates the early fire alarm with a sensitive fire response time (∼3.78 s) and an excellent response repeatability. Moreover, the fire alarm coating also performs the remarkable flame retardancy, smoke suppression and weatherability. This work provides a promising routine to realize the condensed matter as advanced fire sensors, offering insights into fire alarm towards smart phones, cloud service, and a central control system through IoT for fire prevention and protection application.
WeiMing Zhou,Sijia Sun,Yuting Zhang,Shuaiqi Wang,Shuai Zhang,Shengjie Ling,Changtong Mei,Mingzhu Pan
With the rapid development of the 5G era and smart homes, self-healing and self-powered smart fire sensors are considered a promising solution for emerging applications, but fabricating such sensors remains a great challenge. In this study, a highly efficient dynamic crosslinking strategy was developed to construct a self-healing organic–inorganic hybrid material (OIH). More precisely, self-healing OIHs were fabricated through a simple Schiff reaction between chitosan and a Ti 3 O 5 metal–insulator transitional material. The incorporation of multi-crosslinked networks (C N, hydrogen bonds, electrostatic interactions) provided stable charge migration paths for the free movement of protons and hot electrons. Accordingly, the OIH exhibited a substantially enhanced fire-response sensitivity (1.09 s). Moreover, this OIH was capable of self-healing while recovering its fire-warning properties. The OIH intelligent system exhibited good universality on various substrates, such as wood, paper, fiberglass fabrics, and polyurethane (PU) foam. By introducing a self-healing OIH into a fire alarm platform, a highly sensitive warning signal can be sent via Wi-fi or Internet applications. Moreover, a self-powered fire-warning system with triboelectric nanogenerator (TENG) is also demonstrated using OIH. The concept of combining a self-healing and self-powered fire-sensing system may provide potential solutions for applying OIH in emerging applications.
危险品化学品经营许可证（带存储）