Preparation And Gas Sensing Properties Of Polyaniline/phthalocyanine Composites

Efficient,sensitive and low-cost sensing material is a hot spot recently.In this paper,Tetra-?-carboxyphthalocyanine cobalt(II)(TcPcCo)was synthesized by the common liquid template reaction in the presence of ammonium molybdate tetrahydrate.Two kinds of novel PANI/TcPcCo hybrids were prepared by template method and in-situ polymerization.The PANI-TcPcCo was prepared by template method in the presence of TcPcCo,using APS as oxidant;The TcPcCo/a CNT@PANI was prepared by in-situ polymerization,specific process is as follows: First,a CNT were functionalized with TcPcCo by ?-? stacking interactions,then,using TcPcCo/a CNT as template and directing the growth of PANI from the side walls of aCNT resulting in a uniform polymer coating.The products and their intermediates were characterized by MALDI-TOF-MS,UV-Vis FT-IR,TGA,BET,XPS,SEM and TEM,respectively.The gas-sensing performance of the sensors composed of the PANI-TcPcCo or TcPcCo/a CNT@PANI were tested by using a static gas-sensing testing system and the gas-sensing mechanism of them also been systematic discussed.In addition,the relationship between structure and properties of materials were also studied.PANI-TcPcCo and TcPcCo/aCNT@PANI sensor show an enhanced sensitivity response,lower detection limit,fast response and recovery speed and better stability and selectivity in comparison to TcPcCo and PANI sensor.For PANI-TcPcCo sensor,the sensitivity of it to 10 ppm NH3 is about 203.6,which is over 24.41 times higher than that of TcPcCo sensor and over 5.89 times higher than that of PANI sensor,and it also show a low detection limit of 10 ppb.For TcPcCo/a CNT@PANI sensor,the response rate of it to 10 ppm NH3 is about 7 s,which is about one fifth of TcPcCo sensor and about a half of PANI sensor,the recovery rate of it to 10 ppm NH3 is about 9 s,which is about seventeeth of TcPcCo sensor and about one over thirty-three of PANI sensor.