Science Daily February 18, 2022
By using reversibly bonded molecular linkers, gelation can be realized in nanocrystal gels that can be made into responsive and tunable materials. However, there is no experimental means to monitor linking leading to gelation. Researchers at UT Austin developed a metal coordination linkage with a distinct optical signature that allowed them to quantify linking in situ and establish structural and thermodynamic bases for assembly. Because of coupling between linked indium tin oxide nanocrystals, their infrared absorption shifted abruptly at a chemically tunable gelation temperature. They quantified bonding spectroscopically and used molecular simulation to understand temperature-dependent bonding motifs. They found that gel formation was governed by reaching a critical number of effective links that extend the nanocrystal network. The finding could have applications in energy (optical filter for heating, cooling), defense (thermal camouflage)…read more. Open Access TECHNICAL ARTICLE
Quantifying links in thermoreversible nanocrystal assembly… Credit: SCIENCE ADVANCES, 18 Feb 2022, Vol 8, Issue 7