東華大學圖書館 |

Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting = = Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting =/
其他題名:	Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung.
作者:	Song, Angang.
出版者:	Ann Arbor : ProQuest Dissertations & Theses, : 2020,
面頁冊數:	145 p.
附註:	Source: Dissertations Abstracts International, Volume: 83-02, Section: B.
Contained By:	Dissertations Abstracts International83-02B.
標題:	Photovoltaic cells. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28642307
ISBN:	9798522952365

Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting = = Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung.
Song, Angang.

Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting =Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung. - Ann Arbor : ProQuest Dissertations & Theses, 2020 - 145 p.

Source: Dissertations Abstracts International, Volume: 83-02, Section: B.

Thesis (Ph.D.)--Technische Universitaet Berlin (Germany), 2020.

This item must not be sold to any third party vendors.

In the future, the storage of solar energy in the form of chemical bonds is expected to be a key method for solar energy conversion. Photoelectrochemical (PEC) water splitting is one of the most important approaches to convert solar energy into chemical bonds via production of hydrogen. However, there are numerous scientific challenges in developing this PEC water splitting, including the identification of suitable semiconductor materials to use as photoelectrodes with adequate absorption of incident photons, optimization of interfaces between the different layers of the photoelectrodes and the electrolytes, and the development more efficient co-catalysts for both water splitting half-reactions. Among various semiconductor materials that have been considered as photoelectrodes for use in PEC devices, oxide-based photoelectrodes are particularly attractive due to their potential for inexpensive fabrication, environmental friendliness and chemical stability under oxidizing conditions in aqueous solutions compared to other types of semiconductors. This thesis aims to explore new metal oxide semiconductor materials with bandgaps for that allow good visible light absorption and to understand the charge transport properties and interfaces of different layers in the photoelectrodes.P-type CuBi2O4 has recently been reported as a promising photocathode material for photoelectrochemical water reduction due to its optimal optical band gap and positive photocurrent onset potential. However, despite these favorable attributes, CuBi2O4 photocathodes have shown limitations in charge carrier transport within CuBi2O4 and across its interface with n-type fluorine doped tin oxide (FTO) substrate. To overcome the later limitation, a very thin and transparent p-type Cu doped NiO (Cu:NiO) back contact layer is inserted between the FTO substrate and CuBi2O4. It was shown that the addition of a Cu:NiO back contact layer improves the photoelectrochemical performance of CuBi2O4 photocathodes by improving the charge carrier transport across the CuBi2O4-substrate interface. These results illustrate the importance of suitable band alignment and suggest a potential improvement strategy for other oxide-based photocathode materials deposited on FTO substrates.Monoclinic copper vanadate (n-type Cu2V2O7) has a nearly ideal bandgap energy of ∼2.0 eV, which corresponds to a potential solar-to-hydrogen (STH) efficiency of 16%, that makes it a promising candidate as a top absorber in a tandem photoelectrochemical (PEC) device. However, Cu2V2O7 photoanodes have not yet demonstrated high photoconversion efficiencies, and the factors that limit the efficiency have not yet been fully identified. In this thesis, the key physical and photoelectrochemical properties of Cu2V2O7 photoanodes, such as optical band gap, doping type, flat-band potential, band positions, charge carrier transport, chemical composition, chemical stability, and faradaic efficiency for O2 evolution are established. The photoelectrochemical performance of Cu2V2O7 photoanodes was found to be strongly limited by poor charge carrier separation efficiency. Time-resolved microwave conductivity (TRMC) measurements revealed that the low mobility (∼3.5 x 10-3 cm2 V-1 s-1) and short hole diffusion length (∼28 nm) are the main reason for its fast recombination. In addition, cobalt phosphate (Co-Pi) was used as a water oxidation co-catalyst to overcome the slow water oxidation kinetics that partially limit the performance of Cu2V2O7.

ISBN: 9798522952365Subjects--Topical Terms:

604818
Photovoltaic cells.

Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting = = Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung.
LDR:09353nmm a2200373 4500 001 2345679
005 20220613063753.5
008 241004s2020 ||||||||||||||||| ||eng d
020 $a 9798522952365
035 $a (MiAaPQ)AAI28642307
035 $a (MiAaPQ)TechBerlin_1130310927
035 $a AAI28642307
040 $a MiAaPQ $c MiAaPQ
100 1 $a Song, Angang. $3 3684662
245 1 0 $a Synthesis and Characterization of Cu-Based Multinary Metal Oxides for Photoelectrochemical Water Splitting = $b Synthese und Charakterisierung von multinaren Metalloxiden auf Cu-Basis fur die photoelektrochemische Wasserspaltung.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2020
300 $a 145 p.
500 $a Source: Dissertations Abstracts International, Volume: 83-02, Section: B.
500 $a Advisor: Van de Krol, Roel ;Fischer, Anna.
502 $a Thesis (Ph.D.)--Technische Universitaet Berlin (Germany), 2020.
506 $a This item must not be sold to any third party vendors.
520 $a In the future, the storage of solar energy in the form of chemical bonds is expected to be a key method for solar energy conversion. Photoelectrochemical (PEC) water splitting is one of the most important approaches to convert solar energy into chemical bonds via production of hydrogen. However, there are numerous scientific challenges in developing this PEC water splitting, including the identification of suitable semiconductor materials to use as photoelectrodes with adequate absorption of incident photons, optimization of interfaces between the different layers of the photoelectrodes and the electrolytes, and the development more efficient co-catalysts for both water splitting half-reactions. Among various semiconductor materials that have been considered as photoelectrodes for use in PEC devices, oxide-based photoelectrodes are particularly attractive due to their potential for inexpensive fabrication, environmental friendliness and chemical stability under oxidizing conditions in aqueous solutions compared to other types of semiconductors. This thesis aims to explore new metal oxide semiconductor materials with bandgaps for that allow good visible light absorption and to understand the charge transport properties and interfaces of different layers in the photoelectrodes.P-type CuBi2O4 has recently been reported as a promising photocathode material for photoelectrochemical water reduction due to its optimal optical band gap and positive photocurrent onset potential. However, despite these favorable attributes, CuBi2O4 photocathodes have shown limitations in charge carrier transport within CuBi2O4 and across its interface with n-type fluorine doped tin oxide (FTO) substrate. To overcome the later limitation, a very thin and transparent p-type Cu doped NiO (Cu:NiO) back contact layer is inserted between the FTO substrate and CuBi2O4. It was shown that the addition of a Cu:NiO back contact layer improves the photoelectrochemical performance of CuBi2O4 photocathodes by improving the charge carrier transport across the CuBi2O4-substrate interface. These results illustrate the importance of suitable band alignment and suggest a potential improvement strategy for other oxide-based photocathode materials deposited on FTO substrates.Monoclinic copper vanadate (n-type Cu2V2O7) has a nearly ideal bandgap energy of ∼2.0 eV, which corresponds to a potential solar-to-hydrogen (STH) efficiency of 16%, that makes it a promising candidate as a top absorber in a tandem photoelectrochemical (PEC) device. However, Cu2V2O7 photoanodes have not yet demonstrated high photoconversion efficiencies, and the factors that limit the efficiency have not yet been fully identified. In this thesis, the key physical and photoelectrochemical properties of Cu2V2O7 photoanodes, such as optical band gap, doping type, flat-band potential, band positions, charge carrier transport, chemical composition, chemical stability, and faradaic efficiency for O2 evolution are established. The photoelectrochemical performance of Cu2V2O7 photoanodes was found to be strongly limited by poor charge carrier separation efficiency. Time-resolved microwave conductivity (TRMC) measurements revealed that the low mobility (∼3.5 x 10-3 cm2 V-1 s-1) and short hole diffusion length (∼28 nm) are the main reason for its fast recombination. In addition, cobalt phosphate (Co-Pi) was used as a water oxidation co-catalyst to overcome the slow water oxidation kinetics that partially limit the performance of Cu2V2O7.
520 $a Die Speicherung von Sonnenenergie in Form von chemischer Bindungen soll in Zukunft eine Schlusselmethode fur die Umwandlung von Sonnenenergie sein. Photoelektrochemische Wasserspaltung (PEC) ist einer der wichtigsten Ansatze, um Sonnenenergie durch Erzeugung von Wasserstoff in chemische Bindungen umzuwandeln. Es gibt jedoch zahlreiche wissenschaftliche Herausforderungen bei der Weiterentwickelung von PEC-Wasserspaltung. Dazu gehoren unter anderem die Identifizierung geeigneter Halbleitermaterialien zur Verwendung als Photoelektroden mit ausreichender Absorbtionsfahigkeit einfallender Photonen, die Optimierung der Grenzflachen zwischen den verschiedenen Schichten der Photoelektroden und den Elektrolyten, sowie die Entwicklung weiterer Effizienter Cokatalysatoren fur beide wasserspaltenden Halbreaktionen. Unter verschiedenen Halbleitermaterialien, die als Photoelektroden fur die Verwendung in PEC in Betracht kommen, sind Photoelektroden auf Oxidbasis aufgrund ihres Potentials fur eine kostengunstige Herstellung, Umweltfreundlichkeit und chemische Stabilitat unter oxidierenden Bedingungen in Wasser im Vergleich zu anderen Arten von Halbleitern besonders attraktiv. Diese Dissertation zielt darauf ab, neue Metalloxidhalbleitermaterialien mit geringeren Bandlucken fur eine erhohte Photonenabsorption zu untersuchen und die Ladungstransporteigenschaften und Grenzflachen verschiedener Schichten in den Photoelektroden zu verstehen.CuBi2O4 vom P-Typ wurde kurzlich aufgrund seiner optimalen optischen Bandlucke und seines positiven Potentials zum Einsetzen des Fotostroms als vielversprechendes Fotokathodenmaterial fur die photoelektrochemische Wasserreduktion beschrieben. Trotz dieser gunstigen Eigenschaften zeigten CuBi2O4 Fotokathoden Einschrankungen beim Ladungstragertransport innerhalb von CuBi2O4 und uber die Grenzflache mit einem fluordotierten n-Typ-Zinnoxidsubstrat (FTO). Um die spatere Einschrankung zu uberwinden, wird eine sehr dunne und transparente p-Typ Cu-dotierte NiO (Cu:NiO) Ruckkontaktschicht zwischen dem FTO Substrat und CuBi2O4 eingefugt. Es stellte sich heraus, dass die Hinzufugung einer Cu:NiO Ruckkontaktschicht die photoelektrochemische Leistung von CuBi2O4-Photokathoden verbessert, indem der Ladungstragertransport uber die CuBi2O4-Substratgrenzflache verbessert wird. Diese Ergebnisse veranschaulichen die Bedeutung einer geeigneten Bandausrichtung und legen eine mogliche Verbesserungsstrategie fur andere, auf FTO-Substraten abgeschiedene Fotokathodenmaterialien auf Oxidbasis nahe.Monoklines Kupfervanadat (Cu2V2O7 vom n-Typ) weist eine ideale optimale Bandluckenenergie von 2,0 eV auf, was einem potenziellen Solar-Wasserstoff-Wirkungsgrad von 16% entspricht und es zu einem vielversprechenden Kandidaten fur den Top-Absorber in einer photoelektrochemischen (PEC) Tandemzelle. Cu2V2O7 Photoanoden haben jedoch noch keine hohen Photoumwandlungseffizienzen gezeigt, und die Faktoren, die die Effizienz begrenzen, wurden noch nicht vollstandig identifiziert. In dieser Arbeit werden die wichtigsten physikalischen und photoelektrochemischen Eigenschaften dieser vielversprechenden Cu2V2O7 Photoanoden wie zum Beispiel die optische Bandlucke, Dotierungstyp, Flachbandpotential, Bandpositionen, Ladungstragertransport, chemische Zusammensetzung, chemische Stabilitat und O2-Entwicklungs-Faraday-Effizienz ermittelt. Es zeigte sich, dass die photoelektrochemische Leistung von Cu2V2O7-Photoanoden durch eine sehr schlechte Ladungstragertrennungseffizienz stark eingeschrankt ist. Zeitaufgeloste Mikrowellenleitfahigkeitsmessungen (TRMC) ergaben, dass die geringe Mobilitat (~3.5 x 10-3 cm2 V-1 s-1) und die kurze Lochdiffusionslange (~28 nm) der Hauptgrund fur die schnelle Rekombination sind. Zusatzlich wurde Kobaltphosphat (Co-Pi) als Wasseroxidations-Cokatalysator verwendet, um die langsame Wasseroxidationskinetik zu uberwinden, die beitragt an die geringe Leistung von Cu2V2O7.Daruber hinaus untersuchen wir eine photoelektrochemische Tandemzelle, die aus einem W:BiVO4-Photoanoden-Topabsorber und einem CuBi2O4-Photokathoden-Bottomabsorber besteht, fur solare Wasserspaltung. Die CuBi2O4-Fotokathode zeigt ein ausergewohnlich positives Einschaltpotential des Fotostroms von ~1,1 V gegenuber RHE; Unabhangig vom elektrochemischen Potential wird jedoch keine nachweisbare Menge an H2 erzeugt, da der groste Teil des Photostroms wahrscheinlich eher zur Photokorrosion von CuBi2O4 als zur H+ -Reduktion fuhrt, selbst wenn Pt oder RuOx als Cokatalysator zugesetzt werden.
590 $a School code: 1119.
650 4 $a Photovoltaic cells. $3 604818
650 4 $a Spectrum analysis. $3 520440
650 4 $a Alternative energy sources. $3 3561089
650 4 $a Semiconductors. $3 516162
650 4 $a Fossil fuels. $3 701525
650 4 $a Alternative energy. $3 3436775
650 4 $a Analytical chemistry. $3 3168300
650 4 $a Cellular biology. $3 3172791
650 4 $a Chemistry. $3 516420
650 4 $a Energy. $3 876794
650 4 $a Optics. $3 517925
690 $a 0363
690 $a 0486
690 $a 0379
690 $a 0485
690 $a 0791
690 $a 0752
710 2 $a Technische Universitaet Berlin (Germany). $3 3480527
773 0 $t Dissertations Abstracts International $g 83-02B.
790 $a 1119
791 $a Ph.D.
792 $a 2020
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28642307