Photocatalytic transformation in aerogel-based optofluidic microreactors

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F18%3A00491749" target="_blank" >RIV/68081731:_____/18:00491749 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1117/12.2292309" target="_blank" >http://dx.doi.org/10.1117/12.2292309</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1117/12.2292309" target="_blank" >10.1117/12.2292309</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Photocatalytic transformation in aerogel-based optofluidic microreactors

Popis výsledku v původním jazyce

Here, we demonstrate a new type of microphotoreactor formed by a liquid-core optofluidic waveguide fabricated inside aerogel monoliths. It consists of microchannels in a monolithic aerogel block with embedded anatase titania photocatalysts. In this reactor system, aerogel confines core liquid within internal channels and, simultaneously, behave as waveguide cladding due to its extremely low refractive index of ∼1. Light is confined in the channels and is guided by total internal reflection (TIR) from the channel walls. We first fabricated L-shaped channels within silica aerogel monoliths (I= 0.22 g/cm3, n=1.06) without photocatalyst for photolysis reactions. Using the light delivered by waveguiding, photolysis reactions of methylene blue (MB) were carried out in these channels. We demonstrated that MB can be efficiently degraded in our optofluidic photoreactor, with the rate of dye photoconversion increasing linearly with increasing power of incident light. For photocatalytic transformation in this reactor system, titania particles were successfully embedded into the mesoporous network of silica aerogels with varying amount of the titania in the structure from 1.7 wt % to 50 % wt. The presence of titania and its desired crystalline structure in aerogel matrix was confirmed by XRF, XRD patterns and SEM images. Band gap of silica-Titania composites was estimated from Tauc plot calculated by Kubelka-Munk function from diffuse reflectance spectra of samples as near expected value of â‰3.2 eV. Photocatalytic activity and kinetic properties for photocatalytic degradation of phenol in the channels were investigated by a constant flow rate, and longer-Term stability of titania was evaluated.

Název v anglickém jazyce

Photocatalytic transformation in aerogel-based optofluidic microreactors

Popis výsledku anglicky

Here, we demonstrate a new type of microphotoreactor formed by a liquid-core optofluidic waveguide fabricated inside aerogel monoliths. It consists of microchannels in a monolithic aerogel block with embedded anatase titania photocatalysts. In this reactor system, aerogel confines core liquid within internal channels and, simultaneously, behave as waveguide cladding due to its extremely low refractive index of ∼1. Light is confined in the channels and is guided by total internal reflection (TIR) from the channel walls. We first fabricated L-shaped channels within silica aerogel monoliths (I= 0.22 g/cm3, n=1.06) without photocatalyst for photolysis reactions. Using the light delivered by waveguiding, photolysis reactions of methylene blue (MB) were carried out in these channels. We demonstrated that MB can be efficiently degraded in our optofluidic photoreactor, with the rate of dye photoconversion increasing linearly with increasing power of incident light. For photocatalytic transformation in this reactor system, titania particles were successfully embedded into the mesoporous network of silica aerogels with varying amount of the titania in the structure from 1.7 wt % to 50 % wt. The presence of titania and its desired crystalline structure in aerogel matrix was confirmed by XRF, XRD patterns and SEM images. Band gap of silica-Titania composites was estimated from Tauc plot calculated by Kubelka-Munk function from diffuse reflectance spectra of samples as near expected value of â‰3.2 eV. Photocatalytic activity and kinetic properties for photocatalytic degradation of phenol in the channels were investigated by a constant flow rate, and longer-Term stability of titania was evaluated.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20402 - Chemical process engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název statě ve sborníku

Integrated Optics: Devices, Materials, and Technologies XXII (Proceedungs of DPIE)

ISBN

978-151061555-7

ISSN

0277-786X

e-ISSN

—

Počet stran výsledku

10

Strana od-do

105352C

Název nakladatele

SPIE

Místo vydání

Bellingham

Místo konání akce

San Francisco

Datum konání akce

29. 1. 2018

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000449770100046