Electrochemically Active Biofilms Assisted Nanomaterial Synthesis for Environmental Applications

Handle URI:
http://hdl.handle.net/10754/626950
Title:
Electrochemically Active Biofilms Assisted Nanomaterial Synthesis for Environmental Applications
Authors:
Ahmed, Elaf ( 0000-0002-1828-4166 )
Abstract:
Nanomaterials have a great potential for environmental applications due to their high surface areas and high reactivity. This dissertation investigated the use of electrochemically active biofilms (EABs) as a synthesis approach for the fabrication and environmental applications of different nanomaterials. Bacteria in EABs generate electrons upon consuming electron donor and have the ability to transport these electrons to solid or insoluble substrates through extracellular electron transport (EET) mechanism. The extracellularly transported electrons, once utilized, can lead to nanoparticle synthesis. In this dissertation, noble metal (i.e., Au, Pd, and Pt) ultra-small nanoparticles (USNPs) were first synthesized with the assistance by the EABs. The assynthesized USNPs had a size range between 2 and 7 nm and exhibited excellent catalytic performance in dye decomposition. Also in this research, a two-dimensional (2D) cobalt nanosheet was successfully synthesized in the presence of EABs. A simple biogenic route led to the transformation of cobalt acetate to produce a green, toxic free homogeneous 2D cobalt nanosheet structure. Further, TiO2 nanotubes were successfully combined with the noble metal USNPs to enhance their photocatalytic activity. In this work, for the first time, the noble metal USNPs were directly reduced and decorated on the internal surfaces of the TiO2 nanotubes structure assisted by the EABs. The USNPs modified TiO2 nanotubes generated significantly improved photoelectrocatatlyic performances. This dissertation shines lights on the use of EABs in ultra-small nanoparticle synthesis.
Advisors:
Wang, Peng ( 0000-0003-0856-0865 )
Committee Member:
Saikaly, Pascal ( 0000-0001-7678-3986 ) ; Lai, Zhiping ( 0000-0001-9555-6009 ) ; Almayouf, Abdullah
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division
Program:
Environmental Science and Engineering
Issue Date:
Dec-2017
Type:
Dissertation
Appears in Collections:
Dissertations

Full metadata record

DC FieldValue Language
dc.contributor.advisorWang, Pengen
dc.contributor.authorAhmed, Elafen
dc.date.accessioned2018-01-30T07:14:21Z-
dc.date.available2018-01-30T07:14:21Z-
dc.date.issued2017-12-
dc.identifier.urihttp://hdl.handle.net/10754/626950-
dc.description.abstractNanomaterials have a great potential for environmental applications due to their high surface areas and high reactivity. This dissertation investigated the use of electrochemically active biofilms (EABs) as a synthesis approach for the fabrication and environmental applications of different nanomaterials. Bacteria in EABs generate electrons upon consuming electron donor and have the ability to transport these electrons to solid or insoluble substrates through extracellular electron transport (EET) mechanism. The extracellularly transported electrons, once utilized, can lead to nanoparticle synthesis. In this dissertation, noble metal (i.e., Au, Pd, and Pt) ultra-small nanoparticles (USNPs) were first synthesized with the assistance by the EABs. The assynthesized USNPs had a size range between 2 and 7 nm and exhibited excellent catalytic performance in dye decomposition. Also in this research, a two-dimensional (2D) cobalt nanosheet was successfully synthesized in the presence of EABs. A simple biogenic route led to the transformation of cobalt acetate to produce a green, toxic free homogeneous 2D cobalt nanosheet structure. Further, TiO2 nanotubes were successfully combined with the noble metal USNPs to enhance their photocatalytic activity. In this work, for the first time, the noble metal USNPs were directly reduced and decorated on the internal surfaces of the TiO2 nanotubes structure assisted by the EABs. The USNPs modified TiO2 nanotubes generated significantly improved photoelectrocatatlyic performances. This dissertation shines lights on the use of EABs in ultra-small nanoparticle synthesis.en
dc.language.isoenen
dc.subjectElectrochemically Biofilmsen
dc.subjectNanomaterialen
dc.subjectPhotocatalysisen
dc.titleElectrochemically Active Biofilms Assisted Nanomaterial Synthesis for Environmental Applicationsen
dc.typeDissertationen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen
dc.contributor.committeememberSaikaly, Pascalen
dc.contributor.committeememberLai, Zhipingen
dc.contributor.committeememberAlmayouf, Abdullahen
thesis.degree.disciplineEnvironmental Science and Engineeringen
thesis.degree.nameDoctor of Philosophyen
dc.person.id118507en
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