Ultrathin Microporous SiO2 Membranes Photodeposited on Hydrogen Evolving Catalysts Enabling Overall Water Splitting

Handle URI:
http://hdl.handle.net/10754/625978
Title:
Ultrathin Microporous SiO2 Membranes Photodeposited on Hydrogen Evolving Catalysts Enabling Overall Water Splitting
Authors:
Bau, Jeremy A.; Takanabe, Kazuhiro ( 0000-0001-5374-9451 )
Abstract:
Semiconductor systems for photocatalytic overall water splitting into H2 and O2 gases typically require metal cocatalyst particles, such as Pt, to efficiently catalyze H2 evolution. However, such metal catalyst surfaces also serve as recombination sites for H2 and O2, forming H2O. We herein report the photon-induced fabrication of microporous SiO2 membranes that can selectively restrict passage of O2 and larger hydrated ions while allowing penetration of protons, water, and H2. The SiO2 layers were selectively photodeposited on Pt nanoparticles on SrTiO3 photocatalyst by using tetramethylammonium (TMA) as a structure-directing agent (SDA), resulting in the formation of core–shell Pt@SiO2 cocatalysts. The resulting photocatalyst exhibited both improved overall water splitting performance under irradiation and with no H2/O2 recombination in the dark. The function of the SiO2 layers was investigated electrochemically by fabricating the SiO2 layers on a Pt electrode via an analogous cathodic deposition protocol. The uniform, dense, yet amorphous layers possess microporosity originating from ring structures formed during the hydrolysis of the silicate precursor in the presence of TMA, suggesting a double-role for TMA in coordinating silicate to cathodic surfaces and in creating a microporous material. The resulting layers were able to function as a molecular sieve, allowing for exclusive H2 generation while excluding unwanted side reactions by O2 or ferricyanide. The SiO2 layer is stable for extended periods of time in photocatalytic conditions, demonstrating promise as a nontoxic material for selective H2 evolution.
KAUST Department:
KAUST Catalysis Center (KCC); Physical Sciences and Engineering (PSE) Division
Citation:
Bau JA, Takanabe K (2017) Ultrathin Microporous SiO2 Membranes Photodeposited on Hydrogen Evolving Catalysts Enabling Overall Water Splitting. ACS Catalysis: 7931–7940. Available: http://dx.doi.org/10.1021/acscatal.7b03017.
Publisher:
American Chemical Society (ACS)
Journal:
ACS Catalysis
Issue Date:
17-Oct-2017
DOI:
10.1021/acscatal.7b03017
Type:
Article
ISSN:
2155-5435; 2155-5435
Sponsors:
This research in this work was supported by the King Abdullah University of Science and Technology (KAUST). We thank Drs. Nini Wei, Dalaver H. Anjum, and Sergey Lopatin for their assistance with electron microscopy. We thank Dr. Nimer Wehbe for performing SIMS measurements. We thank Muhammad Qureshi for his assistance with photocatalysis.
Additional Links:
http://pubs.acs.org/doi/10.1021/acscatal.7b03017
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; KAUST Catalysis Center (KCC)

Full metadata record

DC FieldValue Language
dc.contributor.authorBau, Jeremy A.en
dc.contributor.authorTakanabe, Kazuhiroen
dc.date.accessioned2017-10-30T07:55:31Z-
dc.date.available2017-10-30T07:55:31Z-
dc.date.issued2017-10-17en
dc.identifier.citationBau JA, Takanabe K (2017) Ultrathin Microporous SiO2 Membranes Photodeposited on Hydrogen Evolving Catalysts Enabling Overall Water Splitting. ACS Catalysis: 7931–7940. Available: http://dx.doi.org/10.1021/acscatal.7b03017.en
dc.identifier.issn2155-5435en
dc.identifier.issn2155-5435en
dc.identifier.doi10.1021/acscatal.7b03017en
dc.identifier.urihttp://hdl.handle.net/10754/625978-
dc.description.abstractSemiconductor systems for photocatalytic overall water splitting into H2 and O2 gases typically require metal cocatalyst particles, such as Pt, to efficiently catalyze H2 evolution. However, such metal catalyst surfaces also serve as recombination sites for H2 and O2, forming H2O. We herein report the photon-induced fabrication of microporous SiO2 membranes that can selectively restrict passage of O2 and larger hydrated ions while allowing penetration of protons, water, and H2. The SiO2 layers were selectively photodeposited on Pt nanoparticles on SrTiO3 photocatalyst by using tetramethylammonium (TMA) as a structure-directing agent (SDA), resulting in the formation of core–shell Pt@SiO2 cocatalysts. The resulting photocatalyst exhibited both improved overall water splitting performance under irradiation and with no H2/O2 recombination in the dark. The function of the SiO2 layers was investigated electrochemically by fabricating the SiO2 layers on a Pt electrode via an analogous cathodic deposition protocol. The uniform, dense, yet amorphous layers possess microporosity originating from ring structures formed during the hydrolysis of the silicate precursor in the presence of TMA, suggesting a double-role for TMA in coordinating silicate to cathodic surfaces and in creating a microporous material. The resulting layers were able to function as a molecular sieve, allowing for exclusive H2 generation while excluding unwanted side reactions by O2 or ferricyanide. The SiO2 layer is stable for extended periods of time in photocatalytic conditions, demonstrating promise as a nontoxic material for selective H2 evolution.en
dc.description.sponsorshipThis research in this work was supported by the King Abdullah University of Science and Technology (KAUST). We thank Drs. Nini Wei, Dalaver H. Anjum, and Sergey Lopatin for their assistance with electron microscopy. We thank Dr. Nimer Wehbe for performing SIMS measurements. We thank Muhammad Qureshi for his assistance with photocatalysis.en
dc.publisherAmerican Chemical Society (ACS)en
dc.relation.urlhttp://pubs.acs.org/doi/10.1021/acscatal.7b03017en
dc.rightsThis is an open access article published under a Creative Commons Non-Commercial No Derivative Works (CC-BY-NC-ND) Attribution License, which permits copying and redistribution of the article, and creation of adaptations, all for non-commercial purposes.en
dc.rights.urihttp://pubs.acs.org/page/policy/authorchoice_ccbyncnd_termsofuse.htmlen
dc.subjectelectrocatalysisen
dc.subjecthydrogenen
dc.subjectmembraneen
dc.subjectoverall water splittingen
dc.subjectphotocatalysisen
dc.subjectSiO2en
dc.subjectstructure directing agenten
dc.titleUltrathin Microporous SiO2 Membranes Photodeposited on Hydrogen Evolving Catalysts Enabling Overall Water Splittingen
dc.typeArticleen
dc.contributor.departmentKAUST Catalysis Center (KCC)en
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalACS Catalysisen
dc.eprint.versionPublisher's Version/PDFen
kaust.authorBau, Jeremy A.en
kaust.authorTakanabe, Kazuhiroen
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