Naslov
The interplay of dissolution and surface reactions at the solid materials in an aqueous electrolyte solution

Autori
Preočanin, Tajana ; Namjesnik, Danijel ; Barišić, Antun ; Klačić, Tin ; Lützenkirchen, Johannes

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
International Conference on Applications of Multi- scale Approaches in Environmental Chemistry / - , 2019, 54-54

Skup
International Conference on Applications of Multi- scale Approaches in Environmental Chemistry

Mjesto i datum
Rennes, Francuska, 23.04.2019. - 25.04.2019

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Surfaces ; electrolyte solutions ; pH ; quartz ; fluorite ; PTFE ; surface potential ; active sites ; electrical interfacial layer (EIL)

Sažetak
The processes at the solid surface / aqueous electrolyte solution play an important role in environmental surface chemistry. The interplay of surface dissolution and surface transformation with the reactions of active surface sites and distribution of ions between the interfacial region and the bulk of the solution will be discussed. Different solid surface will be considered: (i) (0001) quartz surface Si02 - an example of a rather soluble oxide in basic region. In the aqueous electrolyte solution silicon atoms at the quartz surface react with water molecules and form amphoteric silanol surface sites. Consequently, the quartz interfacial properties, i.e. the surface charge and surface potential, are pH dependent. (ii) (111) fluorite surface CaF2 - an example of the semi- soluble mineral which dissolves in the aqueous solution in a series of elementary steps including the reaction of surface groups with H+ ions. Consequently, fluorite interfacial properties Le. the surface charge and surface potential are pH dependent. (iii) polytetrafluoroethylene(PTFE) - an example of a clearly hydrophobic material which does not bear surface functional sites. However, due to the hydrophobicity water dipoles are repelled from the surfaces and the orientation of water molecules is less random than in the bulk of the solution. Such ordering and the resulting distribution of water molecules and ions in the vicinity of the surface cause the formation of an electrical interfacial layer (ElL). Surprisingly, the ion distribution and interfacial properties of the PTFE are also pH dependent. In our research we combine different experimental methods and modelling of thermodynamics and kinetics of the surface reactions.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA