水悬浮液中二氧化碳诱导的介电表面剧烈放电

Peter Vogel, David Beyer, Christian Holm, Thomas Palberg
{"title":"水悬浮液中二氧化碳诱导的介电表面剧烈放电","authors":"Peter Vogel, David Beyer, Christian Holm, Thomas Palberg","doi":"arxiv-2409.03049","DOIUrl":null,"url":null,"abstract":"We study the influence of airborne CO2 on the charge state of carboxylate\nstabilized polymer latex particles suspended in aqueous electrolytes. We\ncombine conductometric experiments interpreted in terms of Hessinger's\nconductivity model with Poisson-Boltzmann cell (PBC) model calculations with\ncharge regulation boundary conditions. Without CO2, a minority of the weakly\nacidic surface groups are dissociated and only a fraction of the total number\nof counter-ions actually contribute to conductivity. The remaining counter-ions\nexchange freely with added other ions like Na+, K+ or Cs+. From the\nPBC-calculations we infer a corresponding pKa of 4.26 as well as a renormalized\ncharge in reasonably good agreement with the number of freely mobile\ncounter-ions. Equilibration of salt- and CO2-free suspensions against ambient\nair leads to a drastic de-charging, which exceeds by far the expected effects\nof to dissolved CO2 and its dissociation products. Further, no\ncounter-ion-exchange is observed. To reproduce the experimental findings, we\nhave to assume an effective pKa of 6.48. This direct influence of CO2 on the\nstate of surface group dissociation explains our recent finding of a\nCO2-induced decrease of the {\\zeta}-potential and supports the suggestion of an\nadditional charge regulation caused by molecular CO2. Given the importance of\ncharged surfaces in contact with aqueous electrolytes, we anticipate that our\nobservations bear substantial theoretical challenges and important implications\nfor applications ranging from desalination to bio-membranes.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"CO2-induced Drastic Decharging of Dielectric Surfaces in Aqueous Suspensions\",\"authors\":\"Peter Vogel, David Beyer, Christian Holm, Thomas Palberg\",\"doi\":\"arxiv-2409.03049\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We study the influence of airborne CO2 on the charge state of carboxylate\\nstabilized polymer latex particles suspended in aqueous electrolytes. We\\ncombine conductometric experiments interpreted in terms of Hessinger's\\nconductivity model with Poisson-Boltzmann cell (PBC) model calculations with\\ncharge regulation boundary conditions. Without CO2, a minority of the weakly\\nacidic surface groups are dissociated and only a fraction of the total number\\nof counter-ions actually contribute to conductivity. The remaining counter-ions\\nexchange freely with added other ions like Na+, K+ or Cs+. From the\\nPBC-calculations we infer a corresponding pKa of 4.26 as well as a renormalized\\ncharge in reasonably good agreement with the number of freely mobile\\ncounter-ions. Equilibration of salt- and CO2-free suspensions against ambient\\nair leads to a drastic de-charging, which exceeds by far the expected effects\\nof to dissolved CO2 and its dissociation products. Further, no\\ncounter-ion-exchange is observed. To reproduce the experimental findings, we\\nhave to assume an effective pKa of 6.48. This direct influence of CO2 on the\\nstate of surface group dissociation explains our recent finding of a\\nCO2-induced decrease of the {\\\\zeta}-potential and supports the suggestion of an\\nadditional charge regulation caused by molecular CO2. Given the importance of\\ncharged surfaces in contact with aqueous electrolytes, we anticipate that our\\nobservations bear substantial theoretical challenges and important implications\\nfor applications ranging from desalination to bio-membranes.\",\"PeriodicalId\":501146,\"journal\":{\"name\":\"arXiv - PHYS - Soft Condensed Matter\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - PHYS - Soft Condensed Matter\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2409.03049\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Soft Condensed Matter","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.03049","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0

摘要

我们研究了空气中的二氧化碳对悬浮在水性电解质中的羧基稳定聚合物乳胶颗粒电荷状态的影响。我们将根据赫辛格电导率模型解释的电导实验与带有电荷调节边界条件的泊松-玻尔兹曼电池(PBC)模型计算相结合。在没有二氧化碳的情况下,少数弱酸性表面基团被解离,只有一小部分反离子对电导率有实际贡献。剩余的反离子会与 Na+、K+ 或 Cs+ 等其他离子自由交换。根据 PBC 计算,我们推断相应的 pKa 为 4.26,重正化电荷与自由移动的反离子数量相当吻合。将不含盐和二氧化碳的悬浮液在环境空气中平衡会导致剧烈的去电荷现象,这种现象远远超出了溶解的二氧化碳及其解离产物的预期影响。此外,没有观察到反离子交换。为了再现实验结果,我们必须假设有效 pKa 为 6.48。二氧化碳对表面基团解离状态的这种直接影响解释了我们最近发现的二氧化碳诱导的{\zeta}电位下降,并支持了由分子二氧化碳引起的附加电荷调节的观点。鉴于与水电解质接触的带电表面的重要性,我们预计我们的观察结果将对从海水淡化到生物膜的应用带来巨大的理论挑战和重要影响。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
CO2-induced Drastic Decharging of Dielectric Surfaces in Aqueous Suspensions
We study the influence of airborne CO2 on the charge state of carboxylate stabilized polymer latex particles suspended in aqueous electrolytes. We combine conductometric experiments interpreted in terms of Hessinger's conductivity model with Poisson-Boltzmann cell (PBC) model calculations with charge regulation boundary conditions. Without CO2, a minority of the weakly acidic surface groups are dissociated and only a fraction of the total number of counter-ions actually contribute to conductivity. The remaining counter-ions exchange freely with added other ions like Na+, K+ or Cs+. From the PBC-calculations we infer a corresponding pKa of 4.26 as well as a renormalized charge in reasonably good agreement with the number of freely mobile counter-ions. Equilibration of salt- and CO2-free suspensions against ambient air leads to a drastic de-charging, which exceeds by far the expected effects of to dissolved CO2 and its dissociation products. Further, no counter-ion-exchange is observed. To reproduce the experimental findings, we have to assume an effective pKa of 6.48. This direct influence of CO2 on the state of surface group dissociation explains our recent finding of a CO2-induced decrease of the {\zeta}-potential and supports the suggestion of an additional charge regulation caused by molecular CO2. Given the importance of charged surfaces in contact with aqueous electrolytes, we anticipate that our observations bear substantial theoretical challenges and important implications for applications ranging from desalination to bio-membranes.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信