title: Surface characterization of electrodeposited silver on activated carbon for bactericidal purposes.
abstract: The use of an electrochemical reactor operated under different flow conditions to deposit silver from aqueous AgNO(3) solutions and tartaric acid as an organic additive on a commercial activated carbon with ultimate bactericidal applications in water purification processes is presented. The characterization of carbon/silver samples was studied by BET, FTIR, X-ray diffraction, XPS, and SEM techniques. The bactericidal activity of the carbon/silver samples was tested on drinking water samples inoculated with E. coli. A reduction of carbon surface area was detected and was caused by increased amounts of silver deposited on carbon samples. Adherent silver deposits were obtained on the carbon/silver samples. X-ray diffraction studies of carbon with electrodeposited silver showed two different preferential deposition planes, [111] and [220]. The FTIR results confirm the presence of carboxyl, phenolic, quinone, and ether surface groups. The XPS results suggest the formation of Ag(2)O and AgO surface species and confirm the reduction of silver to the metallic form. Antimicrobial activity toward E. coli indicated reductions by up to 7 orders of magnitude in the log CFU/mL in just 10 min contact time and for silver contents of 2.47 wt%.
authors.affiliation: Chemical Engineering Department, University of Guadalajara, Blvd. Marcelino García Barragán #1451, Guadalajara, Jalisco 44430, Mexico.
authors.forename: Hector
authors.initials: H
authors.lastname: Ortiz-Ibarra
authors.forename: Norberto
authors.initials: N
authors.lastname: Casillas
authors.forename: Victor
authors.initials: V
authors.lastname: Soto
authors.forename: Maximiliano
authors.initials: M
authors.lastname: Barcena-Soto
authors.forename: Refugio
authors.initials: R
authors.lastname: Torres-Vitela
authors.forename: Wencel
authors.initials: W
authors.lastname: de la Cruz
authors.forename: Sergio
authors.initials: S
authors.lastname: Gómez-Salazar
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods; D004926:Escherichia coli / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D010984:Platinum / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D012835:Silver Nitrate / Q000737:chemistry; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D012834:Silver; D010984:Platinum; D002244:Carbon; D012835:Silver Nitrate