Study Of Ordered Assembled Structures Of Amphiphilic Metalloporphyrin At Water/Air Interface And In Solution

Porphyrins and metalloporphyrins have attracted more interest duing to their well properties of catalysis,optics,electrics,biology,etc.And they show potential applications in many fields,such as biomedicine,nanoreactor and so on.Some water-soluble porphyrins could self-assemble into aggregates with various patterns, such as,vesicle,nanoparticle,nanorod,nanotube,etc.At the same time,they can also interact with surfactant,block-copolymer,biological macromolecule,microemulsion, nanoscale polyoxometalate and to produce aggregates.In this paper,we studied the ordered self-assembly structures of different porphyrins systems in detail from points as follows:1.We synthesized an amphiphilic manganese complex of 5,10,15,20 -tetrakis-4 -oxy(2-stearic acid) phenylporphyrin Mn(â…¢)-TPP(-COOH) according to the synthesis route of literature.And the experimental data are consistent with the reported ones of the literature.And then we obtained the ordered,homogeneous honeycomb structures at the air/water interface by evaporating solvent.This kind of honeycomb structures are studied by transmission electron microscopy(TEM), scanning electron microscopy(SEM),high resolution-TEM(HRTEM),atomic force microscopy(AFM) etc.,and we further studied the formation mechanism of honeycomb film.We also investigated the hydrophobic characteristic and electrochemical behavior of the honeycomb films,experimental data show that for the appending honeycomb films on the flat glass surface,the water contact angle increases to around 110.5°and the ordered honeycomb film possesses catalytic activity for the reduction of oxygen in acidic condition.2.Bilayer vesicles of Mn(â…¢)-TPP(-COOH) self-assembled in nonaqueous organic solvents CHCl₃/CH₃OH(v/v,4:1) are studied.Unlike conventional vesicles,these vesicles can stably exist instead of breaking when transferred to solid substrates after evaporating solvent completely.We observed the aggregates by transmission electron microscopy,scanning electron microscopy,dynamic laser scattering,and the mechanism of the self-assembly of Mn(â…¢)-TPP(-COOH) in mixed solvent of CHCl₃/CH₃OH was discussed primarily.That is,hydrophobic interactions,Ï€-Ï€stacking with adjacent molecules and hydrogen bonds are the main driving forces for forming the porphyrin vesicle structures.And a typical bilayer vesicle model is proposed on the basis of the experimental data.