水-有机溶剂混合溶剂中的双电层：50%乙二醇中的二氧化钛。

Electric Double Layer in Water-Organic Mixed Solvents: Titania in 50% Ethylene Glycol.

机构信息

Laboratory of Electrochemistry, Lublin University of Technology, 20618 Lublin, Poland.

出版信息

Molecules. 2022 Mar 27;27(7):2162. doi: 10.3390/molecules27072162.

DOI:10.3390/molecules27072162

PMID:35408560

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9000690/

Abstract

Ethylene glycol (EG) and its mixtures with water are popular components of nanofluids used as heat transfer fluids. The stability of nanofluids against coagulation is correlated with their zeta potential. The electrophoretic mobility of titania nanoparticles in 50-50 w/w EG was studied as a function of the concentration of various solutes. HCl, NaOH, SDS and CTMABr at concentrations up to 0.01 M are strong electrolytes in 50% EG, that is, the conductance of their solutions is proportional to the concentration. HCl, NaOH and CTMABr were very efficient in inducing a high zeta potential for titania in 50% EG. NaOH induced a negative zeta potential in excess of 70 mV, and HCl and CTMABr induced a positive zeta potential in excess of 70 mV at concentrations below 10−4 M. Apparently, HCl, NaOH and CTMABr are also more efficient than SDS in terms of nanofluid stabilization against coagulation. An overdose of base (>1 mM) results in depression of the negative zeta potential. This result may be due to the specific adsorption of sodium on titania from 50% EG.

摘要

乙二醇（EG）及其与水的混合物是用作传热流体的纳米流体的常见成分。纳米流体对凝聚的稳定性与其 ζ 电位有关。研究了二氧化钛纳米粒子在 50-50w/wEG 中的电泳迁移率作为各种溶质浓度的函数。在 50%EG 中，HCl、NaOH、SDS 和 CTMABr 浓度高达 0.01M 是强电解质，即其溶液的电导率与浓度成正比。HCl、NaOH 和 CTMABr 非常有效地在 50%EG 中诱导二氧化钛产生高 ζ 电位。NaOH 在浓度低于 10-4M 时诱导超过 70mV 的负 ζ 电位，HCl 和 CTMABr 诱导超过 70mV 的正 ζ 电位。显然，HCl、NaOH 和 CTMABr 在稳定纳米流体防止凝聚方面比 SDS 更有效。过量的碱（>1mM）会导致负 ζ 电位降低。这一结果可能是由于从 50%EG 中，钠离子对二氧化钛的特异性吸附。