聚(3,4-亚乙基二氧噻吩)/聚(苯乙烯磺酸盐)高导电柔性薄膜制备及掺杂效应研究  

Highly Conductive and Flexible Poly(3,4-Ethylenedioxythiophene)/Poly(Styrene Sulfonate)Film and Investigation of the Effects of Doping

作　　者：吴法霖 张天才[2] 王永凤[2] 邓贤明 唐继海[2] 林牧春 孙宽[1] 张林 倪士文 吴欣睿 WU Fa-lin;ZHANG Tian-cai;WANG Yong-feng;DENG Xian-ming;TANG Ji-hai;LIN Mu-chun;SUN Kuan;ZHANG Lin;NI Shi-wen;WU Xin-rui(Key Laboratory of Low-grade Energy Utilization Technologies and Systems,Ministry of Education,Chongqing University,Chongqing 400044,China;Southwest Institute of Technology and Engineering,Chongqing 400050,China;School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Chongqing Jianshe Yamaha Motorcycle Company Limited,Chongqing 400052,China)

机构地区：[1]重庆大学低品位能源利用技术及系统教育部重点实验室,重庆400044 [2]西南技术工程研究所,重庆400039 [3]上海交通大学材料科学与工程学院,上海200240 [4]重庆建设雅马哈摩托车有限公司,重庆400052

出　　处：《表面技术》2023年第12期440-448,共9页Surface Technology

基　　金：国家重点研发计划(2022YFB3803300);国家自然科学基金(62074022)。

摘　　要：目的针对聚(3,4-亚乙基二氧噻吩)/聚(苯乙烯磺酸盐)(PEDOT:PSS)薄膜的电导率低的问题,采用二次掺杂方法,提高薄膜电导率和品质因数(FoM),为制备可打印导电薄膜以及柔性光电器件表面导电层提供技术支撑。方法采用多种无机酸分别与PEDOT:PSS溶液共混的掺杂方法,通过旋涂法在基底上制备透明导电薄膜。利用四点探针法、分光光度计测试系统,对掺杂处理后薄膜的方块电阻、透光率、导电率和品质因数进行测试及分析。利用原子力显微镜(AFM)、X射线光电子能谱(XPS)和霍尔效应测试系统,对薄膜内部结构进行有理分析,总结提升薄膜电导率的原因。结果无机酸对薄膜电导率具有提升作用,通过硫酸的掺杂作用后,电导率可以由0.9 S/cm提高到2216 S/cm,FoM从0.03提高到33;通过焦磷酸掺杂处理后的薄膜,电导率可以提高到1623 S/cm,FoM提高到40。结论掺杂试剂的沸点、解离常数、退火温度以及共混液的黏度都会影响薄膜的光电性能。解离常数越低,更容易解离出氢离子的掺杂试剂,能够与PSS结合形成PSSH,促进PEDOT和PSS分离。沸点低和解离常数小的无机酸掺杂试剂,能够有效提高薄膜的电导率,并能够获得高品质因数的薄膜。PEDOT:PSS通过无机酸改性处理后,减小了PEDOT和PSS之间作用力的同时,提高了薄膜内部PEDOT的相对含量,使PEDOT链变得线性,促进载流子传输,从而使薄膜的电导率提高。Poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate)(PEDOT:PSS)is a new conductive film material.In order to improve the physical properties of the film,an effective secondary doping method is adopted.The conductivity of PEDOT:PSS film was improved by secondary doping with various inorganic acids.The physical properties of doped film were tested and analyzed by four point probe method and UV spectrophotometer.Atomic force microscope(AFM)was used to measure the surface morphology of the film.The internal structure of the film was analyzed by X-ray photoelectron spectroscopy(XPS)and Hall effect testing system.The conductivity of H2SO4-doped film was improved to 2216 S/cm at the concentration of 0.08 mol/L,and the conductivity of H3PO3-doped film can be enhanced to 2033 S/cm.The FoM of film was affected by the thickness,transmittance and quality of film.The film prepared by 0.1 mol/L H4P2O7 shows a transmittance of 82%at 550 nm and the FoM could reach 40,which had potential for commercial application.The conductivity of the film treated with H2SO4,H3PO3,H4P2O7 and H3PO4 was inversely proportional to the dissociation constant of the doped reagent.H+could better combine with PSS,which promoted the separation of PEDOT and PSS.Therefore,conductive PEDOT wrapped by insulating PSS could be exposed to form PEDOT aggregates.The aggregation of PEDOT made the crimped PEDOT chain more linear and the electronic transmission easier.The PKa of doping reagent was not the only factor affecting the conductivity.The PKa of HClO4 was–10,but the conductivity was only 760 S/cm.It was attributed to the increase of the concentration of the HClO4-doped solution,which increased the thickness of the prepared film(361 nm),and the thickness was inversely proportional to the conductivity.AFM test results show that PEDOT and PSS are separated,and PEDOT fibers are formed in the film.XPS characterization results show that the peak intensity ratio of PEDOT and PSS is 0.34 for pristine PEDOT:PSS film.The peak intensity ratio of the HPF6-doped

关 键 词：PEDOT:PSS 无机酸 薄膜 电导率 品质因数 

分 类 号：TB34[一般工业技术—材料科学与工程]