Cation-controlled crystal growth of silver stearate: cryo-TEM investigation of lithium vs sodium stearate.
Cryo-TEM, SAXS, and light microscopy techniques were used to probe the morphology and kinetics of silver stearate self-assembly and crystallization from the reaction of silver nitrate with lithium stearate. Unlike the reaction of sodium stearate with silver nitrate, which proceeds via micelle aggregation, the lithium stearate forms vesicles that drastically change the reaction kinetics of the silver stearate nucleation and self-assembly process. In addition, even with excess silver nitrate present, only about 80% of the lithium stearate can be converted to silver stearate. The presence of the residual lithium stearate inhibits the silver stearate crystal growth process. Consequently, no silver stearate micelle aggregates of any significant size form, unlike the system utilizing sodium stearate. Instead, significantly smaller silver stearate crystals result from lithium stearate compared to the silver stearate crystals from sodium stearate and provide an opportunity to further control silver stearate self-assembly and crystal growth.
Dong
Jingshan
J
Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, USA. dong0034@umn.edu
McCormick
Alon V
AV
Davis
H Ted
HT
Whitcomb
David R
DR
D002412:Cations / Q000737:chemistry; D020285:Cryoelectron Microscopy / Q000379:methods*; D003460:Crystallization; D008094:Lithium / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry*; D013228:Stearates / Q000737:chemistry*; D013499:Surface Properties
D002412:Cations; D009942:Organometallic Compounds; D013228:Stearates; D012834:Silver; D008094:Lithium; D012964:Sodium