Controlling The Assembly Kinetics Of Au(?)-MPA Nanosheets

Supramolecular assemblies have dynamic reversibility due to the weak noncovalent driving forces,and they have properties of stimuli-responsiveness and environmental accumulation.Supramolecular assemblies are usually classified by the assembly driving force,such as,hydrogen bond,coordination bond,host-guest interaction,electrostatic interaction,?-? interaction,hydrophobic interaction,and so on.Au(I)-thiolate coordination polymers,as a special kind of supramolecular building block,not only have the traditional weak interactions(such as,hydrogen bond,coordination interaction,and Van der Waals' force)as the driving forces,but also have the unique aurophilic interaction,which makes the assembly pathway and the structures more complicated,therefore,Au(I)-thiolate can be used as a model system to understand the hierarchical assembly process of biomacromolecules,such as protein and DNA.At present,most of the methods to control the assembly pathway are changing the temperature,concentration,recipee,solvent,and so on.These methods can both change the thermodynamics and the kinetics.And some poinner researches have investigated the role of kinetic parameters,such as ultrasound and light on the assembly process,and it reveals the kinetic parameters have played important role in control of the assembly sizes and size distributions.Here,all the thermodynamic parameters are kept invariable by keeping reactants and solvent unchanged,the reactants mixing sequence and preassembly of reactants was used to tune the assembly kinetics.Results show that the mixing sequence at the very first several seconds can greatly change the size of the product because of the change of the size of the precusor;pre-assemble of the reactants to different sized precursors can separate aggregation and crystallization and change the conversion rates and yields,based on the above results,we exploit a method of synthesizing Au(I)/Ag(I)-MPA hybrid assemblies by mixing pre-assemblied Au(I)-MPA and Ag(I)-MPA.The study aims to study the role of kinetic parameters on the assembly of Au(I)-thiolate without changing the thermodynamic parameters,and the kinetic parameters can play very huge role in a complicated assembly system.