Solvent Segregation Driven Gel (SeedGel) Formation via Self-assembly of Nanoparticles in Binary Solvents
ORAL
Abstract
Due to the high specific surface area and interconnected channels, bicontinuous structures have found a broad range of applications in energy storage, membrane science, and biomaterials. Here, we report a new type of colloidal gel, solvent segregation driven gel (SeedGel), that successfully stabilizes such bicontinuous channels. SeedGel consists of alternating particle and solvent domains, which is driven by the solvent phase separation using temperature. A model system of nanoparticles in a binary solvent mixture of water/ 2,6-lutidine is used to demonstrate the formation of the SeedGel. Interestingly, the binary solvent also leads to bicontinuous structures with water (particles favor) enriched in the particle domain. Excellent thermo-reversibility and structure reproducibility over multi-length scales are confirmed by the studies using ultra-small angle neutron scattering (USANS) and small-angle neutron scattering (SANS). Ramping rate is shown to accurately control the channel width of the bicontinuous domains. Different binary solvents can be used to adjust the gelation temperature of SeedGel, making it adaptable for various applications over a wide temperature range. And the refractive index of these domains can also be manipulated by controlling the partition of the solvents in different domains to gain interesting optical properties.
*We acknowledge the financial support from Cooperative Agreement No. 70NANB12H239 and 70NANB10H256 of the National Institute of Standards and Technology (NIST), the U.S. Department of Commerce. Access to NGB 30 m SANS, VSANS and BT-5 USANS were provided by the Center for High Resolution Neutron Scattering (CHRNS), a partnership between the National Institute of Standards and Technology and the National Science Foundation under Agreement No. DMR-1508249.
–
Publication:1. Xi, Y.; Lankone, R. S.; Sung, L.-P.; Liu, Y. Tunable Thermo-Reversible Bicontinuous Nanoparticle Gel Driven by the Binary Solvent Segregation. Nat. Commun. 2021, 12 (1), 910 DOI: 10.1038/s41467-020-20701-3. 2. Xi, Y.; Leão, J. B.; Ye, Q.; Lankone, R. S.; Sung, L.-P.; Liu, Y. Controlling Bicontinuous Structures through a Solvent Segregation-Driven Gel. Langmuir 2021, 37 (6), 2170–2178 DOI: 10.1021/acs.langmuir.0c03472.
