Plasmonic- Photonic Hybrids by Freeze- Casting: Ag decorated 1D and 2D TiO2 Hollow Patterned Nanostructures for Green Photocatalysis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F44555601%3A13420%2F19%3A43895094" target="_blank" >RIV/44555601:13420/19:43895094 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/plasmonicphotonic-hybrids-by-freezecasting-ag-decorated-1d-and-2d-tio2-hollow-patterned-nanostructures-for-green-photocatalysis/56C300ADF73F2DE62B906AF8425E2504" target="_blank" >https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/plasmonicphotonic-hybrids-by-freezecasting-ag-decorated-1d-and-2d-tio2-hollow-patterned-nanostructures-for-green-photocatalysis/56C300ADF73F2DE62B906AF8425E2504</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1017/S1431927619011449" target="_blank" >10.1017/S1431927619011449</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Plasmonic- Photonic Hybrids by Freeze- Casting: Ag decorated 1D and 2D TiO2 Hollow Patterned Nanostructures for Green Photocatalysis

Popis výsledku v původním jazyce

Titania, in particular anatase TiO2 has been extensively used in photoelectrochemistry (dye-sensitized TiO2 electrodes for water splitting) and photocatalysis (TiO2 based catalysts for degradation of emerging environmental substances). TiO2 is the most studied photocatalyst because of its non-toxicity and chemical stability [1]. On the other hand, high recombination rate of the photogenarated electron-hole pairs restricts the photocatalytic activity of TiO2 and novel strategies to design effective TiO2 photocatalysts for enhanced light harvesting could be developed. Several reports have been announced to increase the lifetime of the generated electron-hole pairs by loading of noble, Ag metal nanoparticles (NPs) onto the TiO2 surface, which can act as electron trapping centers. In this work we demonstrated the capability of the ice-templating phenomenon, reported also as the icesegregation- induced self-assembly (ISISA) process, for synthesis of Ag modified TiO2 materials with highly sophisticated structures - 1DTiO2 microrods (MRs) and 2DTiO2 nanosheets - hierarchical materials demonstrating different levels of spatial organization. 1DTiO2 MRs and 2DTiO2 NSHTs with dense polyhedral stacked 3D nanovoids were prepared by using simple freeze-casting (a cryolyophilization) procedure [2, 3]. Hierarchical morphologies of nanocavities start to appear at temperature higher than 800 oC and are strongly influenced by polymorph TiO2 evolution competing reactions. The morphology of Ag modified 1DTiO2 sample annealed at 800 oC is shown in Fig. 1a-c. Photoelectrochemical measurements were conducted with deposited of as obtained sample on FTO glass substrates. The layer was then dried and fixed to the electrode surface by heating (500oC, 1hr). The cyclic voltammetry was studied between bias potentials -0.5 and +0.5 eV with Pt counter electrode, Ag/AgCl reference electrode in 0.5M H2SO4 as an electrolyte. 2cm2 of the electrode surface with 0,66 mg of the deposited sample was irradiated by Vis light (100W). Efficient hydrogen generation on Pt and oxygen on working electrodes were observed (Fig. 1d). The best catalysts exhibited enhanced photocatalitic activity under UV light in decomposition of 4 chlorophenol was Ag modified 2D TiO2 sample annealed at 800oC (Ag_2DTiO2/800). The photocatalitic activity of Ag_2DTiO2/800 sample, with nanocavities is much higher than that of TiO2 without nanocavities. The extra ordinary photoactivity could be explained by evenly distributed nanocavities inside perfectly crystalized 2DTiO2 nanocrystals with homogeneously dispersed metallic Ag on their surface. Figure 2 revealed microstructure of Ag_2DTiO2/800.

Název v anglickém jazyce

Plasmonic- Photonic Hybrids by Freeze- Casting: Ag decorated 1D and 2D TiO2 Hollow Patterned Nanostructures for Green Photocatalysis

Popis výsledku anglicky

Titania, in particular anatase TiO2 has been extensively used in photoelectrochemistry (dye-sensitized TiO2 electrodes for water splitting) and photocatalysis (TiO2 based catalysts for degradation of emerging environmental substances). TiO2 is the most studied photocatalyst because of its non-toxicity and chemical stability [1]. On the other hand, high recombination rate of the photogenarated electron-hole pairs restricts the photocatalytic activity of TiO2 and novel strategies to design effective TiO2 photocatalysts for enhanced light harvesting could be developed. Several reports have been announced to increase the lifetime of the generated electron-hole pairs by loading of noble, Ag metal nanoparticles (NPs) onto the TiO2 surface, which can act as electron trapping centers. In this work we demonstrated the capability of the ice-templating phenomenon, reported also as the icesegregation- induced self-assembly (ISISA) process, for synthesis of Ag modified TiO2 materials with highly sophisticated structures - 1DTiO2 microrods (MRs) and 2DTiO2 nanosheets - hierarchical materials demonstrating different levels of spatial organization. 1DTiO2 MRs and 2DTiO2 NSHTs with dense polyhedral stacked 3D nanovoids were prepared by using simple freeze-casting (a cryolyophilization) procedure [2, 3]. Hierarchical morphologies of nanocavities start to appear at temperature higher than 800 oC and are strongly influenced by polymorph TiO2 evolution competing reactions. The morphology of Ag modified 1DTiO2 sample annealed at 800 oC is shown in Fig. 1a-c. Photoelectrochemical measurements were conducted with deposited of as obtained sample on FTO glass substrates. The layer was then dried and fixed to the electrode surface by heating (500oC, 1hr). The cyclic voltammetry was studied between bias potentials -0.5 and +0.5 eV with Pt counter electrode, Ag/AgCl reference electrode in 0.5M H2SO4 as an electrolyte. 2cm2 of the electrode surface with 0,66 mg of the deposited sample was irradiated by Vis light (100W). Efficient hydrogen generation on Pt and oxygen on working electrodes were observed (Fig. 1d). The best catalysts exhibited enhanced photocatalitic activity under UV light in decomposition of 4 chlorophenol was Ag modified 2D TiO2 sample annealed at 800oC (Ag_2DTiO2/800). The photocatalitic activity of Ag_2DTiO2/800 sample, with nanocavities is much higher than that of TiO2 without nanocavities. The extra ordinary photoactivity could be explained by evenly distributed nanocavities inside perfectly crystalized 2DTiO2 nanocrystals with homogeneously dispersed metallic Ag on their surface. Figure 2 revealed microstructure of Ag_2DTiO2/800.

Druh

J_ost - Ostatní články v recenzovaných periodicích

CEP obor

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OECD FORD obor

21001 - Nano-materials (production and properties)

Projekt

—

Návaznosti

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

Microscopy and Microanalysis

ISSN

1431-9276

e-ISSN

1435-8115

Svazek periodika

2019

Číslo periodika v rámci svazku

25(S2)

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

2

Strana od-do

2142-2143

Kód UT WoS článku

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EID výsledku v databázi Scopus

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