Preparation Of Poly (O-phenylendiamine) Micro/Nano Structures And Their Application

Ortho-phenylendiamine?o PD?,with two adjacent –NH2 groups in the benzene ring,is one of typical aniline derivatives.o PD has huge advantages in the respects of post processing and modification because o PD owns more active sites than aniline.Meanwhile,Po PD?o-phenylendiamine?can be applied in many fields of catalysis,sensors,electrochemical display,energy storage,due to its special conductive property.The investigations of Po PD were mainly focused on the mechanism of polymerization,the process of oxidation-reduction,the mechanism of self-assembly,the properties of photoelectric and their applications,etc.The synthesis methods of micro/nano structure Po PD materials include chemical oxidation method,coprecipitation method,microfluidic method,hydrothermal method,etc.The researches on the synthesis and applications of special structured Po PD are the hot issue in this field.Herein,Po PD with controllable morphology was synthesized successfully by chemical oxidation method and electro formation method.The disassembly and fluorescence property of Po PD materials by different post-processing proceses were studied.The PoPD structures were used for fluorescence probes,electric catalysts and energy storage.Micro/nano structured Po PD materials were prepared by chemical oxidation method using CuCl2 as oxidant agent.In the process of polymerization,PoPD oligomers did not aggregate because of the electrostatic repulsion.The addition of high salt solution in the reaction system increased the ionic strength of solution,thus promoting the self-assembly process of PoPD oligomers.Many different morphologies of Po PD,such as belts,fibers,nano beams,clusters and ultra long fibers,were prepared by controlling the mole ratio of reaction reagent.The formation mechanism of Po PD structures was explained based on experimental results.The transformation of Po PD morphology by protonation and deprotonation process was studied.After deprotonation process,the ultra long PoPD fibers can emit green fluorescence under UV light??ex=418nm?.The fluorescence efficiency of the fluorescent Po PD fibers was 56.2%.The pH fluorescence probe based on the sensitivity to deprotonation process of ultra long Po PD fibers was fabricated,which showed good bleaching resistance to UV light.The Po PD pH fluorescence probe exhibited a good stability.To avoid the influence of heavy metal ions in the self-assembly of Po PD,the micro/nano structured Po PD was prepared by chemical oxidation method with H₂O₂ as a green oxidant agent.NaCl was introduced to regulate the ionic strength of the solution,thus promoting the aggregation of PoPD oligomers.The square prism shaped Po PD fibers,spheres,clusters and sea urchin structures were obtained.The length,width,bending and bifurcation of Po PD structures were controlled.Poly p-phenylenediamine?PpPD?materials were prepared through chemical oxidation using H₂O₂ as oxidant,which demonstrated the morphology of the PpPD materials can be controlled through this method.Through a variety of post-processing disassembly of Po PD,the disassembly process models were proposed.The fluorescence property of Po PD fibers was studied after the deprotonation process.The ratio of C to N in Po PD structures was controlled by high temperature calcination.PoPD electrode materials were prepared for supercapacitor.The cycle stability of the S-400,S-500,S-600 electrodes showed an obviously attenuation with the cycle number increasing.After 1000 cycles,the capacities of S-700 and S-800 electrode still maintained about 95% of the initial capacity with a good stability.Noble metal oxidant H₂PdCl₄ was introduced to prepare PoPD materials,and Pd doped Po PD micro/nano structures were prepared successfully.The square prism shaped tubes,hexagon tubes,belts and spheres Pd doped Po PD micro/nano structures were obtained.Through controlling the reaction conditions,the on-demand controlling Pd doped Po PD micro/nano structures were achieved.The formation process of the square prism shaped Pd-doped-PoPD tubes was investigated.After high temperature?600??calcination of the square prism shaped Pd doped Po PD tubes,square prism shaped Pd tubes?SP-Pd-MTs?were obtained,which consisted of large amount of Pd spheres.The Pd tubes were used to electrocatalyze ethanol.The EASA of commercial Pt/C and SP-Pd-MTs are 26.7m2/g and 48.2m2/g,respectively.The EASA of SP-Pd-MTs was larger than the commercial Pt/C,probably because the large amount of holes in the wall.The current density of the SP-Pd-MTs and commercial Pt/C in the forward scan were 146mA/cm2 and 48.5mA/cm2,respectively.The larger EASA value and current density demonstrated that SP-Pd-MTs had better electro catalysis.In the self-assembly process,electric field was introduced to control the self-assembly process of the Po PD oligomers to obtain Po PD half-tubes.Through controlling the distance between the electrode,the structures of the PoPD materials can be controlled.The tubular structure of the Po PD gradually disappeared with the increase of the distance between two electrodes.In an uniform electric field,the Po PD oligomers were assembled to PoPD fibers.The electric field was simulated using COMSOL Multiphysics software to explain the formation mechanism of PoPD half-tubes.After deprotonation process,the PoPD half-tubes can emit green fluorescence.After post-processing with ethanol,the Po PD half-tubes can emit red fluorescence.The fluorescence efficiency of the green and red fluorescence was 40.5% and 52.4%,respectively.