title: High-Performance Capacitive Deionization Disinfection of Water with Graphene Oxide-graft-Quaternized Chitosan Nanohybrid Electrode Coating.
abstract: Water disinfection materials should ideally be broad-spectrum-active, nonleachable, and noncontaminating to the liquid needing sterilization. Herein, we demonstrate a high-performance capacitive deionization disinfection (CDID) electrode made by coating an activated carbon (AC) electrode with cationic nanohybrids of graphene oxide-graft-quaternized chitosan (GO-QC). Our GO-QC/AC CDID electrode can achieve at least 99.9999% killing (i.e., 6 log reduction) of Escherichia coli in water flowing continuously through the CDID cell. Without the GO-QC coating, the AC electrode alone cannot kill the bacteria and adsorbs a much smaller fraction (<82.8 ± 1.8%) of E. coli from the same biocontaminated water. Our CDID process consists of alternating cycles of water disinfection followed by electrode regeneration, each a few minutes duration, so that this water disinfection process can be continuous and it only needs a small electrode voltage (2 V). With a typical brackish water biocontamination (with 10(4) CFU mL(-1) bacteria), the GO-QC/AC electrodes can kill 99.99% of the E. coli in water for 5 h. The disinfecting GO-QC is securely attached on the AC electrode surface, so that it is noncontaminating to water, unlike many other chemicals used today. The GO-QC nanohybrids have excellent intrinsic antimicrobial properties in suspension form. Further, the GO component contributes toward the needed surface conductivity of the CDID electrode. This CDID process offers an economical method toward ultrafast, contaminant-free, and continuous killing of bacteria in biocontaminated water. The proposed strategy introduces a green in situ disinfectant approach for water purification.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Yilei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Ahmed G
authors.initials: AG
authors.lastname: El-Deen
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.|Centre for Biomedical Engineering and Regenerative Medicine, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an 710049, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Bernice H L
authors.initials: BH
authors.lastname: Oh
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Zanru
authors.initials: Z
authors.lastname: Guo
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Mya Mya
authors.initials: MM
authors.lastname: Khin
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.
authors.forename: Yogesh S
authors.initials: YS
authors.lastname: Vikhe
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Lee Kong Chian School of Medicine, Nanyang Technological University , Singapore 308232.
authors.forename: Rebecca G
authors.initials: RG
authors.lastname: Hu
authors.affiliation: Food Process Engineering Laboratory, Agrotechnology and Food Sciences Group, Wageningen University , Wageningen 6708 WG, The Netherlands.
authors.forename: Remko M
authors.initials: RM
authors.lastname: Boom
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University , Singapore 637551.|School of Biological Sciences, Nanyang Technological University , Singapore 637551.
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Kline
authors.affiliation: Lee Kong Chian School of Medicine, Nanyang Technological University , Singapore 308232.
authors.forename: David L
authors.initials: DL
authors.lastname: Becker
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Duan
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University , Singapore 637459.|Centre for Antimicrobial Bioengineering, Nanyang Technological University , Singapore 637459.
authors.forename: Mary B
authors.initials: MB
authors.lastname: Chan-Park
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D004203:Disinfection / Q000191:economics / Q000295:instrumentation*; D004553:Electric Conductivity; D004566:Electrodes; D004867:Equipment Design; D004926:Escherichia coli / Q000302:isolation & purification*; D006108:Graphite / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry; D014871:Water Microbiology; D018508:Water Purification / Q000191:economics / Q000295:instrumentation*
chemical_list: D010087:Oxides; D006108:Graphite; D048271:Chitosan
keywords: antimicrobial; capacitive deionization; cationic; contact-active; graphene oxide; quaternary chitosan; water disinfection