Maskless microfabrication of nanowire-decorated porous membrane for rapid purification of contaminated water

Due to widespread droughts and population increase, the rapid and sustainable purification of contaminated water is of major interest to human beings. Toward this end, this paper reports a handheld and efficient purification system using maskless micro/nanofabrication techniques. A porous polymer membrane decorated with nanomaterials was tailored to physically filter pollutants in contaminated water. To create the porous polymer membrane, curable polymer and black sugar powder were used for a facile and cost-effective fabrication method. The black sugar particles linked in cured polymer were selectively dissolved in hot water, forming micro-sized pores for filtering out pollutants. The nanowires were hydrothermally grown onto the porous membrane to further improve the purification performance by capturing finer pollutants between nanowires. The combination of nanowires and 50-wt% concentration of black sugar particle, forming a porosity of ~ 27.71% showed the minimum residual rate (i.e., weight of pollutants in purified water) of 0.981 mg/ml. This study supports the use of hierarchical porous membrane for the efficient and sustainable purification of contaminated water within a short period time.