文献类型：期刊文献

英文题名：Understanding surface charge regulation in silica nanopores

作者：Yang, Jie[1,2];Su, Haiping[1,2];Lian, Cheng[1,2,3];Shang, Yazhuo[1,2];Liu, Honglai[1,2];Wu, Jianzhong[4]

机构：[1]East China Univ Sci & Technol, Shanghai Engn Res Ctr Hierarch Nanomat, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]Univ Utrecht, Ctr Extreme Matter & Emergent Phenomena, Inst Theoret Phys, Princetonpl 5, NL-3584 CC Utrecht, Netherlands;[4]Univ Calif Riverside, Dept Chem & Environm Engn, Riverside, CA 92521 USA

年份：2020

卷号：22

期号：27

起止页码：15373

外文期刊名：PHYSICAL CHEMISTRY CHEMICAL PHYSICS

收录：;EI(收录号：20203108988257);WOS:【SCI-EXPANDED(收录号:WOS:000549894000020)】；

基金：This research was sponsored by the financial support by the National Natural Science Foundation of China (No. 91834301 and 21808055), China Postdoctoral Science Foundation (2019M651416), and Shanghai Sailing Program (18YF1405400, 19YF1411700). J. W. thanks the financial support from the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Basic Energy Sciences. C. L. acknowledges the helpful discussion with R. van Roij.

语种：英文

外文关键词：Charge density - Electrolytes - Nanopores - Silica - Surface charge - Surface reactions - Density functional theory

摘要：Nanoporous silica is used in a wide variety of applications, ranging from bioanalytical tools and materials for energy storage and conversion as well as separation devices. The surface charge density of nanopores is not easily measured by experiment yet plays a vital role in the performance and functioning of silica nanopores. Herein, we report a theoretical model to describe charge regulation in silica nanopores by combining the surface-reaction model and the classical density functional theory (CDFT). The theoretical predictions provide quantitative insights into the effects of pH, electrolyte concentration, and pore size on the surface charge density and electric double layer structure. With a fixed pore size, the surface charge density increases with both pH and the bulk salt concentration similar to that for an open surface. At fixed pH and salt concentration, the surface charge density rises with the pore size until it reaches the bulk asymptotic value when the surface interactions become negligible. At high pH, the surface charge density is mainly determined by the ratio of the Debye screening length to the pore size (lambda(D)/D).