Open AccessSynergistic engineering of hole transport materials in perovskite solar cells
Author(s) -
Mabrouk Sally,
Bahrami Behzad,
Elbohy Hytham,
Reza Khan Mamun,
Gurung Ashim,
Liang Mao,
Wu Fan,
Wang Mingtai,
Yang Shangfeng,
Qiao Qiquan
Publication year - 2020
Publication title -
infomat
Language(s) - English
Resource type - Journals
ISSN - 2567-3165
DOI - 10.1002/inf2.12062
Subject(s) - pedot:pss , materials science , perovskite (structure) , doping , dopant , conductive polymer , graphene , dielectric spectroscopy , open circuit voltage , conductive atomic force microscopy , conductivity , chemical engineering , crystallinity , nanotechnology , polyaniline , nanocomposite , optoelectronics , layer (electronics) , electrochemistry , composite material , polymer , atomic force microscopy , polymerization , chemistry , voltage , electrode , physics , quantum mechanics , engineering
In this work, methylammonium lead triiodide (CH 3 NH 3 PbI 3 ) perovskite solar cells with efficiencies higher than 18% were achieved using a new nanocomposite hole transport layer (HTL) by doping poly(ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) with a mixed dopant of polyaniline (PANI) and graphene oxide (GO). A synergistic engineering between GO, PANI, and PEDOT:PSS was accomplished to introduce additional energy levels between perovskite and PEDOT:PSS and increase the conductivity of PEDOT:PSS. Kelvin probe force microscope results confirmed that adding GO to PEDOT:PSS/PANI composite significantly reduced the average surface potential. This increased the open circuit voltage ( V oc ) to 1.05 V for the GO/PEDOT:PSS/PANI nanocomposite perovskite solar cells from the pristine PEDOT:PSS ( V oc = 0.95 V) and PEDOT:PSS/PANI ( V oc = 0.99 V). In addition, adding PANI to the HTLs substantially enhanced short circuit current density ( J sc ). This was supported by the current sensing‐atomic force microscopy (CS‐AFM) and conductivity measurements. The PANI doped films showed superior electrical conductivity compared with those without PANI as indicated by CS‐AFM results. PANI can fill the gaps between the microflakes of GO and give rise to more compact hole transport material (HTM) layer. This led to a higher J sc after doping with PANI, which was consistent with the incident photon‐to‐current efficiency and electrochemical impedance spectroscopy results. The results of X‐ray diffraction (XRD) and AFM indicated the GO/PANI doped HTMs significantly improved the crystallinity, topography, and crystal size of the perovskite film grown on their surface. A higher efficiency of 18.12% for p‐i‐n perovskite solar cells has been obtained by adding the mixed dopant of GO, PANI, and PEDOT:PSS, demonstrating better stability than the pristine PEDOT:PSS cell.