Extended hierarchical solvent perturbations from curved surfaces of mesoporous silica particles in a deep eutectic solvent

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:520

Article

Hammons, Joshua A.¹  Zhang, Fan²  Ilaysky, Jan³ 

[1] Lawrence Livermore Natl Lab, Mat Sci Div, 7000 East Ave, Livermore, CA 94550 USA

[2] NIST, Mat Measurement Sci Div, 100 Bur Dr, Gaithersburg, MD 20899 USA

[3] Argonne Natl Lab, Adv Photon Source, 9700 S Cass Ave, Lemont, IL 60439 USA

关键词: Electrostatic stabilization;    Deep eutectic solvents;    Pore activity;    Nanoparticle stabilization;    Small angle scattering;    Mesoporous silica;    Drug delivery;    Green technology;    Meso-scale solvent fluctuations;   

DOI  :  10.1016/j.jcis.2018.02.078

来源: Elsevier

【 摘 要 】

Hypothesis: Many applications of deep eutectic solvents (DES) rely on exploitation of their unique yet complex liquid structures. Due to the ionic nature of the DES components, their diffuse structures are perturbed in the presence of a charged surface. We hypothesize that it is possible to perturb the bulk DES structure far (>100 nm) from a curved, charged surface with mesoscopic dimensions. Experiments: We performed in situ, synchrotron-based ultra-small angle X-ray scattering (USAXS) experiments to study the solvent distribution near the surface of charged mesoporous silica particles (MPS) (approximate to 0.5 mu m in diameter) suspended in both water and a common type of DES (1:2 choline Cl-:ethylene glycol). Findings: A careful USAXS analysis reveals that the perturbation of electron density distribution within the DES extends approximate to 1 mu m beyond the particle surface, and that this perturbation can be manipulated by the addition of salt ions (AgCl). The concentration of the pore-filling fluid is greatly reduced in the DES. Notably, we extracted the real-space structures of these fluctuations from the USAXS data using a simulated annealing approach that does not require a priori knowledge about the scattering form factor, and can be generalized to a wide range of complex small-angle scattering problems. (C) 2018 Elsevier Inc. All rights reserved.

【 授权许可】

Free