Department of Chemistry, University of Connecticut , 55 North Eagleville Rd, Storrs, Connecticut 06269-3060, United States.
Kazakh National Research Technical University , 22 Satpayev St., Almaty 050013, Kazakhstan.
ACS Nano. 2016 Dec 27;10(12):11397-11406. doi: 10.1021/acsnano.6b06735. Epub 2016 Nov 22.
Nanoreactors were created by entrapping homogeneous catalysts in hollow nanocapsules with 200 nm diameter and semipermeable nanometer-thin shells. The capsules were produced by the polymerization of hydrophobic monomers in the hydrophobic interior of the bilayers of self-assembled surfactant vesicles. Controlled nanopores in the shells of nanocapsules ensured long-term retention of the catalysts coupled with the rapid flow of substrates and products in and out of nanocapsules. The study evaluated the effect of encapsulation on the catalytic activity and stability of five different catalysts. Comparison of kinetics of five diverse reactions performed in five different solvents revealed the same reaction rates for free and encapsulated catalysts. Identical reaction kinetics confirmed that placement of catalysts in the homogeneous interior of polymer nanocapsules did not compromise catalytic efficiency. Encapsulated organometallic catalysts showed no loss of metal ions from nanocapsules suggesting stabilization of the complexes was provided by nanocapsules. Controlled permeability of the shells of nanocapsules enabled size-selective catalytic reactions.
纳米反应器是通过将均相催化剂包埋在具有 200nm 直径和半透纳米薄壳的中空纳米胶囊中来制备的。这些胶囊是通过在自组装表面活性剂囊泡的双层疏水性内部聚合疏水性单体而产生的。纳米胶囊壳中的可控纳米孔确保了催化剂的长期保留，同时促进了底物和产物快速进出纳米胶囊。该研究评估了封装对五种不同催化剂的催化活性和稳定性的影响。在五种不同溶剂中进行的五种不同反应的动力学比较表明，游离催化剂和封装催化剂的反应速率相同。相同的反应动力学证实，将催化剂置于聚合物纳米胶囊的均相内部不会影响催化效率。封装的有机金属催化剂没有金属离子从纳米胶囊中流失，这表明纳米胶囊提供了配合物的稳定性。纳米胶囊壳的可控渗透性使尺寸选择性催化反应成为可能。
