Silver loaded nanofibrous membrane with high catalytic performance for 4-nitrophenol under continuous gravity-driven filtration was developed in this study. A polydopamine (PDA) microsphere and nanofiber coordinated composite structure was fabricated through an in situ PDA synthesis to achieve a high catalyst loading and controllable residence time of 4-nitrophenol. The incorporated PDA microspheres played an important role for the enhancement of catalytic performance due to the increased surface area (23% increase compared with PAN and PAN-PDAs-Ag) and reduced membrane porosity. Silver loading amount and the residence time of 4-nitrophenol was increased by more than 108% (from 1.2 wt% to 2.5 wt%) and 45% (from 0.79 s to 1.15 s) when comparing with PAN-PDAc-Ag and PAN-PDAs-Ag nanofibrous membrane. The conversion rate of 4-nitrophenol in a gravity-driven filtration process was as high as 97% when PAN-PDAs-Ag nanofibrous membrane was used, which was much higher than the PAN-PDAc-Ag membrane (80%). In addition, the PAN-PDAs-Ag nanofibrous membrane exhibited excellent recycle performance, the conversion rate was maintained as high as 93% after five times of reuse. The microsphere and nanofiber coordinated structure with enhanced surface area and controllable residence time of contaminants proposed in this study might advance the real applications of electrospun nanofibrous membrane for catalytic removal of contaminants.

本研究开发了在连续重力驱动的过滤条件下对4-硝基苯酚具有高催化性能的载银纳米纤维膜。通过原位制备聚多巴胺（PDA）微球和纳米纤维配位的复合结构PDA合成可实现较高的催化剂负载量和4-硝基苯酚的可控停留时间。由于增加的表面积（与PAN和PAN-PDAs-Ag相比增加了23％）和降低的膜孔隙率，并入的PDA微球在提高催化性能方面发挥了重要作用。与PAN-PDAc-Ag和PAN-相比，4-硝基苯酚的载银量和4-硝基苯酚的停留时间分别增加了108％（从1.2 wt％至2.5 wt％）和45％（从0.79 s至1.15 s）。 PDAs-Ag纳米纤维膜。当使用PAN-PDAs-Ag纳米纤维膜时，在重力驱动的过滤过程中4-硝基苯酚的转化率高达97％，远高于PAN-PDAc-Ag膜（80％）。此外，PAN-PDAs-Ag纳米纤维膜还具有出色的回收性能，重复使用五次后，转换率可保持高达93％。在这项研究中提出的具有增加的表面积和可控的污染物停留时间的微球和纳米纤维协调的结构可能促进电纺纳米纤维膜在催化去除污染物方面的实际应用。