Frequent outbreaks of emerging infectious diseases (EIDs) make personal protective filter media in high demand. Electrospun nanofibrous materials are proved to be very effective in resisting virus-containing fine particles owing to their small fiber diameters; however, hindered by the intrinsic close-packing character of fine fibers, electrospun filters suffer from a relatively high air resistance, thereby poor breathing comfort. Here, we report a biomimetic and one-step strategy to create ultrafine and curly wool-like nanofibers, named nano-wool, which exhibit fluffy assembly architecture and powerful electret effect. By achieving the online self-crimp and in-situ charging of nanofibers, the curly electret nano-wool shows a small diameter of ~0.6 μm (two orders of magnitude lower than natural wool: ~20 μm) and an ultrahigh porosity of 98.7% simultaneously, together with an ultrahigh surface potential of 13260 V (one order of magnitude higher than previous filters). The structural advantages and powerful electret effect enable nano-wool to show excellent filtration efficacy (>99.995% for PM 0.3 ) and low air resistance (55 Pa). Additionally, nano-wool can be easily scaled up, not only holding great industrial prospect in personal protective respirators, but also paving the way for developing next-generation wool in a cost-efficient and multifunctional form.
A core-shell structured USY-xTT@NiMo catalyst was prepared through thermal treatment method and evaluated for the catalytic hydrodesulfurization (HDS) performance toward dibenzothiophene (DBT). The shell assembled from NiMoS nano-wool provided abundant active site. This nano-wool morphology and core-shell structure resulted in the catalyst with enhanced specific surface area, pore volume, lower interaction between the support and active metals, and facilitated metal dispersion. In addition, the nano-wool morphology and core-shell structure also promoted the degree of sulfurization and provided more sulfur vacancies, which enhanced the HDS performance of the corresponding catalysts. An efficient USY-16TT@NiMo catalyst with shorter slab lengths (average 2.50 nm), higher average stacking number (3.37 layers), and more edge active sites was assembled, which showed superior k HDS value of DBT up to 8.29 × 10 −4 mol g −1 h −1 and high direct desulfurization selectivity to be 88 %.
危险品化学品经营许可证（带存储）