Manipulating the molecular structure of PEDOT chains through controlling the viscosity of PEDOT:PSS solutions to improve the photovoltaic performance of CH3NH3PbI3 solar cells

Sheng Hsiung Chang, Wei Nien Chen, Cheng Chiang Chen, Shih Chieh Yeh, Hsin Ming Cheng, Zong Liang Tseng, Lung Chien Chen, Kuo Yuan Chiu, Wen Ti Wu, Chin Ti Chen, Sheng Hui Chen, Chun Guey Wu

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

A series of alcohols (methanol, ethanol and isopropyl alcohol) were added to poly(3,4-ethylenedioxythiophene): (polystyrene sulfonate) (PEDOT: PSS) aqueous solutions in order to manipulate the molecular structure of the PEDOT chains in PEDOT: PSS hole transporting materials (HTMs) and thus to improve the power conversion efficiency of CH3NH3PbI3 based solar cells. The structural and electronic characteristics of the resultant PEDOT: PSS HTMs were analyzed using atomic-force microscopy, contact angle measurement, Raman scattering spectrometry and photoelectron spectrometry. The properties of the PEDOT: PSS thin films could be controlled by tuning the viscosity of the PEDOT: PSS solutions. High viscosity PEDOT: PSS solutions resulted in linear structured PEDOT chains, which increased the work function of the PEDOT: PSS HTMs thereby improving the open-circuit voltage of the CH3NH3PbI3 solar cells. The surface roughness and surface free energy of the PEDOT: PSS HTMs influence the structural properties of CH3NH3PbI3 thin films, which determines the exciton dissociation at the CH3NH3PbI3/PEDOT: PSS interface (short-circuit current density) and the carrier recombination at the CH3NH3PbI3/[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) interface (fill factor). In addition, it is predicted that the power conversion efficiency can be further improved by increasing the crystallinity of the CH3NH3PbI3 thin film.

Original languageEnglish
Pages (from-to)7-13
Number of pages7
JournalSolar Energy Materials and Solar Cells
Volume161
DOIs
StatePublished - 1 Mar 2017

Keywords

  • CHNHPbI
  • Energy transfer
  • PEDOT:PSS
  • Photovoltaics
  • Surface properties

Fingerprint

Dive into the research topics of 'Manipulating the molecular structure of PEDOT chains through controlling the viscosity of PEDOT:PSS solutions to improve the photovoltaic performance of CH3NH3PbI3 solar cells'. Together they form a unique fingerprint.

Cite this