Ti doped hematite photoanodes: Protective coverage by titania overlayers

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F23%3A00574889" target="_blank" >RIV/61388955:_____/23:00574889 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/23:43926550 RIV/60461373:22350/23:43926550

Výsledek na webu

<a href="https://hdl.handle.net/11104/0344817" target="_blank" >https://hdl.handle.net/11104/0344817</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jphotochem.2023.115026" target="_blank" >10.1016/j.jphotochem.2023.115026</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Ti doped hematite photoanodes: Protective coverage by titania overlayers

Popis výsledku v původním jazyce

In this work, the photoresponse of Ti doped hematite electrodes was optimized by adjusting the thickness and the level of doping. The electrodes were then covered by a TiO2 overlayer by dip coating (DC) or by atomic layer deposition (ALD) to improve chemical stability. Coverage of hematite by a dip-coated sol–gel TiO2 film of thickness up to 135 nm resulted only in a small decrease in photocurrent (by about 30 %). A similar decrease in photocurrent (about 25 %) was observed after the coverage by a very thin (2 nm) ALD TiO2 film while the increase of the thickness to 8 nm led to almost complete suppression of photocurrent. This behaviour can be explained by the different morphology and structure of the overlayers. Although the surface morphology of sol–gel TiO2 films was very smooth and dense, penetration of such films by the electrolyte occurred even for a thickness of 135 nm. On the other hand, much thinner ALD TiO2 films (8 nm) exhibited almost no electrolyte penetration. Such different blocking properties of the two TiO2 overlayers are in direct agreement with the observed dissolution rate in acidic media – the better the blocking properties of an overlayer the better the chemical stability of stratified hematite/titania photoelectrode.

Název v anglickém jazyce

Ti doped hematite photoanodes: Protective coverage by titania overlayers

Popis výsledku anglicky

In this work, the photoresponse of Ti doped hematite electrodes was optimized by adjusting the thickness and the level of doping. The electrodes were then covered by a TiO2 overlayer by dip coating (DC) or by atomic layer deposition (ALD) to improve chemical stability. Coverage of hematite by a dip-coated sol–gel TiO2 film of thickness up to 135 nm resulted only in a small decrease in photocurrent (by about 30 %). A similar decrease in photocurrent (about 25 %) was observed after the coverage by a very thin (2 nm) ALD TiO2 film while the increase of the thickness to 8 nm led to almost complete suppression of photocurrent. This behaviour can be explained by the different morphology and structure of the overlayers. Although the surface morphology of sol–gel TiO2 films was very smooth and dense, penetration of such films by the electrolyte occurred even for a thickness of 135 nm. On the other hand, much thinner ALD TiO2 films (8 nm) exhibited almost no electrolyte penetration. Such different blocking properties of the two TiO2 overlayers are in direct agreement with the observed dissolution rate in acidic media – the better the blocking properties of an overlayer the better the chemical stability of stratified hematite/titania photoelectrode.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Photochemistry and Photobiology A-Chemistry

ISSN

1010-6030

e-ISSN

1873-2666

Svazek periodika

445

Číslo periodika v rámci svazku

NOV 2023

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

8

Strana od-do

115026

Kód UT WoS článku

001069222900001

EID výsledku v databázi Scopus

2-s2.0-85167447889