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Koncepce dynamického aktivního centra v heterogenní fotokatalytické oxidační reakci.

SYSNO ASEP	0505588
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	Koncepce dynamického aktivního centra v heterogenní fotokatalytické oxidační reakci.
Title	The Concept of a Dynamic Active Site in a Heterogeneous Photocatalytic Oxidation Reaction.
Author(s)	Klusoň, Petr (UCHP-M)_{RID, ORCID, SAI} Krýsa, J. (CZ) Stavárek, Petr (UCHP-M)_{RID, ORCID, SAI} Hejda, Stanislav (UCHP-M)_{RID, ORCID, SAI} Vychodilová, Hana (UCHP-M)_{RID, SAI} Dzik, P. (CZ) Veselý, M. (CZ) Krystyník, Pavel (UCHP-M)_{RID, SAI, ORCID}
Source Title	Chemické listy. - : Česká společnost chemická - ISSN 0009-2770 Roč. 113, č. 6 (2019), s. 391-396
Number of pages	6 s.
Language	cze - Czech
Country	CZ - Czech Republic
Keywords	active centre ; reaction rate ; photon
Subject RIV	CI - Industrial Chemistry, Chemical Engineering
OECD category	Chemical process engineering
R&D Projects	VI20162019037 GA MV - Ministry of Interior (MV)
Method of publishing	Limited access
Institutional support	UCHP-M - RVO:67985858
UT WOS	000473231800007
EID SCOPUS	85069471784
Annotation	Zavedení koncepce dynamického aktivního centra (DAS) v heterogenní fotokatalytické oxidaci umožňuje pro materiály, u nichž byl tento typ reakčního místa identifikován, využít standardní kinetické algoritmy a rovnice používané v heterogenní katalýze. Použití DAS je však z praktických důvodů spíše omezeno na částicové tenké vrstvy, u kterých lze bez větších experimentálních potíží provést světlem indukovaný elektrochemický experiment. Jeho cílem je především vyhodnotit kvalitativní charakter odezvy světlocitlivé vrstvy na přítomnost fotonů. Kvantitativní popis je rovněž důležitý, ovšem pro objektivizaci existence DAS není klíčový.
Description in English	In this communication we wished to introduce the concept of a dynamic active site (CDAS) for oxidation of thin films photocatalysts as a certain analogy to the common conceptions of active sites in heterogeneous catalysts. The main intention was to show an experimental algorithm which should be applied if two (or more) different thin film photocatalysts are to be compared in a particular reaction. It is unfortunately very common that the performances of two particular photocatalysts are compared and conclusions are drawn, but such a comparison is incorrect from principle reasons. It was shown here that the existence of a dynamic active site must be validated first for both (or more) catalytic species being compared, and only if it is successful at this stage. standard kinetic data treatment and their comparisons are possible. Polarization curves provided by the linear voltammetry (I-E/current-voltage) reflect the ability of the light sensitive semicon-ducting films to generate the carriers (electrons and holes) upon illumination. The stability of the generated photocurrent level (the plateau) indicates the same rate of the formation of charges and their recombination. If this is true, the electrochemical system occurs in the state of dynamic equilibrium. Under model conditions, it is thus possible to assess whether or not a particular photocatalytic material tends to generate h+ species in the same rate as it vanishes. If the answer is positive, the holes h+ might be formally referred to as standard active sites since upon fixed illumination their abundance is constant in time.
Workplace	Institute of Chemical Process Fundamentals
Contact	Eva Jirsová, jirsova@icpf.cas.cz, Tel.: 220 390 227
Year of Publishing	2020
Electronic address	http://hdl.handle.net/11104/0298432

Number of the records: 1