Graphical BP/MoS 2 heterojunction is prepared by solvothermal method using NMP, BP nanosheets and (NH 4 ) 2 MoS 4 . Under NIR irradiation, BP/MoS 2 can be heated up to 51.8 °C within 5 minutes by photothermal conversion. In addition, the existence of ⋅O 2 − and 1 O 2 in BP/MoS 2 -NIR system is verified to sterilize efficiently. With a loading content of 10 wt % MoS 2 , bacterial cells, especially drug-resistant bacteria (10 6 cfu ⋅ mL −1 ) completely can lose the viability within 10 min of NIR irradiation. In this research, a high-efficiency nano-fungicide with synergistic effect was obtained by combining polycrystalline MoS 2 with layered nano-BP to form heterojunction, which had a new photothermal-photocatalytic antibacterial mechanism to Gram-positive bacteria, Gram-negative and drug-resistance bacteria under NIR. BP/MoS 2 whose lethality of bacteria could reach nearly 100 % at 400 μg/L, exhibited the highest photothermal lysis efficiency against E. coli, B. pumilus and A. baumannii. It was found that the heterojunction could be heated up to 51.8 °C within 5 minutes by photothermal conversion, and it also had an excellent performance of photothermal cycle. High temperature and stability of the material endowed it with an outstanding and long-lasting bactericidal effect. In addition, a series of in vitro free radical experiments was designed, the existence of ⋅O 2 − and 1 O 2 in BP/MoS 2 -NIR system was verified. And the Way of ROS production and the mechanism of action were discussed by EPR test. Subsequently, two mechanisms of synergistic antibacterial action were summarized, that is, abundant ROS and high temperature could destroy cell wall damage and lysis of bacteria effectively. This study provides a theoretical basis for the synergistic antibacterial action of NIR photothermal and photocatalysis of BP system.
Design and exploitation of smart fire-warning devices with ultrasensitive response capability are always an urgent need for effective fire protection. Herein, a nano-filler (BP-MoS 2 ) is prepared by ball milling black phosphorene and molybdenum disulfide and added into the graphene oxide (GO) film to fabricate a multifunctional film with high fire resistance and rapid response ability. When the addition of BP-MoS 2 is 20.0 wt%, the GO/BP-MoS 2 20.0 shows an excellent flame retardancy. The residual char rate is improved from 46.60% to 66.65%, and its peak of heat release rate (pHRR) value has reduced from 599.92 W g −1 to 274.00 W g −1 , resulting in a 54.33% decrease, which is attributed to the ultra-fast catalytic char formation and synergistic flame retardancy of BP and MoS 2 . Meanwhile, the composite film can still maintain the original shape within 15 s of ignition. More interestingly, when encountering a flame attack, it reveals an ultra-fast fire warning response (about 1 s), which is attributed to the fast carbonization after contacting with flame. Such approach offers a novel perspective for the preparation of intelligent fire alarm devices with ultra-fast response ability.
Design novel flame retardant and mechanical enhancing agents of waterborne polyurethane (WPU) is a crucial issue for expanding its application. Herein, BP@MoS 2 hybrids was designed and prepared to enhance the fire safety and mechanical properties of WPU and BP@MoS 2 possessed a novel cactus-like structure. BP@MoS 2 was prepared in a two-step method including preparation of black phosphorus (BP) sheets by chemical vapor transfer method and preparation of BP@MoS 2 by in situ growth of molybdenum disulfide (MoS 2 ). with adding 2.0wt% BP@MoS 2 , the tensile strength and fracture strength of WPU/BP@MoS 2 -2.0 increase by 57.7% and 36.5%, respectively. The peak value of heat release rate (PHRR) and total smoke production (TSP) of WPU/BP@MoS 2 -2.0 also reduce by 50.3% and 52.0%, which indicates that fire safety and mechanical performance of WPU/BP@MoS 2 -2.0 is effectively enhanced. Meanwhile, BP@MoS 2 has both condensed phase and gas phase flame retardant effect on WPU. In condensed phase, the residue char of WPU/BP@MoS 2 is with excellent physical barrier effect. In gas phase, BP@MoS 2 can inhibit the generation of flammable volatiles such as aromatic and aliphatic compounds during burning of WPU/BP@MoS 2 , thereby inhibiting the heat release and smoke release behavior of WPU/BP@MoS 2 .
危险品化学品经营许可证（带存储）