title: Magnetically ultraresponsive nanoscavengers for next-generation water purification systems.
abstract: The development of sustainable, robust and energy efficient water purification technology is still challenging. Although use of nanoparticles is promising, methods are needed for their efficient recovery post treatment. Here we address this issue by fabrication of magnetically ultraresponsive 'nanoscavengers', nanoparticles containing synthetic antiferromagnetic core layers and functional capping layers. When dispersed in water, the nanoscavengers efficiently interact with contaminants to remove them from the water. They are then quickly collected (<5 min) with a permanent magnet, owing to their magnetically ultraresponsive core layers. Specifically, we demonstrate fabrication and deployment of Ag-capped nanoscavengers for disinfection followed by application of an external magnetic field for separation. We also develop and validate a collision-based model for pathogen inactivation, and propose a cyclical water purification scheme in which nanoscavengers are recovered and recycled for contaminant removal.
authors.affiliation: Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: Mingliang
authors.initials: M
authors.lastname: Zhang
authors.forename: Xing
authors.initials: X
authors.lastname: Xie
authors.forename: Mary
authors.initials: M
authors.lastname: Tang
authors.forename: Craig S
authors.initials: CS
authors.lastname: Criddle
authors.forename: Yi
authors.initials: Y
authors.lastname: Cui
authors.forename: Shan X
authors.initials: SX
authors.lastname: Wang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004203:Disinfection; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification; D060328:Magnetic Phenomena; D059346:Magnets; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000494:pharmacology; D012996:Solutions; D014874:Water Pollutants, Chemical / Q000302:isolation & purification; D018508:Water Purification / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; D012996:Solutions; D014874:Water Pollutants, Chemical; D012834:Silver