Method for continuous fabrication of carbon nanotube networks or membrane materials

Methods and devices are provided for the continuous production of a network of nanotubes or other nanoscale fibers. The method includes making a suspension of nanoscale fibers dispersed in a liquid medium, optionally with surfactant and/or sonication, and filtering the suspension by moving a filter membrane through the suspension, such that the nanoscale fibers are deposited directly on the filter membrane as the fluid medium flows through the filter membrane, thereby forming a continuous membrane of the nanoscale fibers. The deposition of the nanoscale fibers can occur when and where the filter membrane moves into contact with a static, porous filter element or a dynamic, porous filter element. The filtering can be conducted within a magnetic field effective to align the nanoscale fibers, and/or with the aid of vacuum to pull water through the filter membrane, applied pressure to press water though the filter membrane, or a combination thereof.