Please use this identifier to cite or link to this item:
Title: Size and roughness dependent temperature effects on surface charge of silica nanoparticles
Authors: Alan, Büşra Öykü
Barışık, Murat
Keywords: Surface charge density
Silica nanoparticles
Charge regulated surface
Nanoscale surface patterns
Temperature dependence
Issue Date: 2021
Publisher: Elsevier
Abstract: Silica nanoparticles (SNP) with different sizes and surface areas are used in numerous micro/nanofluidic applications, while their surface charge properties play a major role in their function. In many of these applications, SNPs also undergo temperature variation. We present that an increase in temperature yields a substantial increase in SNP surface charge depending on nanoparticle size and surface roughness, which cannot be estimated by existing theory. As a continuation of our earlier work characterizing the deviation of SNP surface charging from theoretical predictions due to curvature and EDL overlap effects, this study presents the differentiation from the theory in temperature dependence under various conditions. As we calculate surface chemistry as a function of local ionic conditions (Charge Regulation), temperature variation changed the equilibrium constants of protonation/deprotonation reactions of the SNP surface, in addition to changes occurring in relative permittivity and ionic mobilities. Results show that variation of SNP surface charge by temperature decreases by decreasing particle size and/or increasing roughness size, compare to theoretical flat plate calculations considering similar temperature-dependent properties and charge regulation on the surface. We characterized these deviations by obtaining an electrokinetic similarity between different systems of various size and roughness at various ionic conditions based on the non-dimensional groups of lambda/DP and lambda/DR. Based on these, we devised a phenomenological model as an extension to the flat plate theory to successfully predict the surface charge of SNPs as a function of the particle size, roughness size, and temperature. The current findings are important for the characterization of SNPs through temperature variations and can also be used to adjust the surface charge of SNPs by tuning the temperature.
ISSN: 0927-7757
Appears in Collections:Mechanical Engineering / Makina Mühendisliği
Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Files in This Item:
File SizeFormat 
1-s2.0-S0927775721012760-main.pdf10.1 MBAdobe PDFView/Open
Show full item record

CORE Recommender


checked on Nov 25, 2023


checked on Jun 19, 2023

Page view(s)

checked on Nov 27, 2023


checked on Nov 27, 2023

Google ScholarTM



Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.