Stable high-performance hybrid perovskite solar cells with ultrathin polythiophene as hole-transporting layer

Ultrathin polythiophene films prepared via electrochemical polymerization is successfully used as the hole-transporting material, substituting conventional HTM-PEDOT:PSS, in planar p-i-n CH3NH3PbI3 perovskite-based solar cells, affording a series of ITO/polythiophene/CH3NH3PbI3/C60/BCP/Ag devices. The ultrathin polythiophene film possesses good transmittance, high conductivity, a smooth surface, high wettability, compatibility with PbI2 DMF solution, and an energy level matching that of the CH3NH3PbI3 perovskite material. A promising power conversion efficiency of about 15.4%, featuring a high fill factor of 0.774, open voltage of 0.99 V, and short-circuit current density of 20.3 mA·cm−2 is obtained. The overall performance of the devices is superior to that of cells using PEDOT:PSS. The differences of solar cells with different hole-transfer materials in charge recombination, charge transport and transfer, and device stability are further investigated and demonstrate that polythiophene is a more effective and promising hole-transporting material. This work provides a simple, prompt, controllable, and economic approach for the preparation of an effective hole-transporting material, which undoubtedly offers an alternative method in the future industrial production of perovskite solar cells.

[1]  Jeffrey A. Christians,et al.  An inorganic hole conductor for organo-lead halide perovskite solar cells. Improved hole conductivity with copper iodide. , 2014, Journal of the American Chemical Society.

[2]  Yaming Yu,et al.  NH2CH═NH2PbI3: An Alternative Organolead Iodide Perovskite Sensitizer for Mesoscopic Solar Cells , 2014 .

[3]  Laura M. Herz,et al.  Electron-Hole Diffusion Lengths Exceeding 1 Micrometer in an Organometal Trihalide Perovskite Absorber , 2013, Science.

[4]  Yang Yang,et al.  Interface engineering of highly efficient perovskite solar cells , 2014, Science.

[5]  Timothy L. Kelly,et al.  Perovskite solar cells with a planar heterojunction structure prepared using room-temperature solution processing techniques , 2013, Nature Photonics.

[6]  Fan Zuo,et al.  Additive Enhanced Crystallization of Solution‐Processed Perovskite for Highly Efficient Planar‐Heterojunction Solar Cells , 2014, Advanced materials.

[7]  Tomas Leijtens,et al.  Carbon nanotube/polymer composites as a highly stable hole collection layer in perovskite solar cells. , 2014, Nano letters.

[8]  Erik M. J. Johansson,et al.  Using a two-step deposition technique to prepare perovskite (CH3NH3PbI3) for thin film solar cells based on ZrO2 and TiO2 mesostructures , 2013 .

[9]  Mohammad Khaja Nazeeruddin,et al.  Efficient inorganic-organic hybrid perovskite solar cells based on pyrene arylamine derivatives as hole-transporting materials. , 2013, Journal of the American Chemical Society.

[10]  C. Brabec,et al.  Interface Engineering of Perovskite Hybrid Solar Cells with Solution-Processed Perylene–Diimide Heterojunctions toward High Performance , 2015 .

[11]  Stephen Z. D. Cheng,et al.  Anisotropic Polythiophene Films with High Conductivity and Good Mechanical Properties via a New Electrochemical Synthesis , 2002 .

[12]  Zhuang Liu,et al.  Efficient planar heterojunction perovskite solar cells employing graphene oxide as hole conductor. , 2014, Nanoscale.

[13]  Chunhui Huang,et al.  High-performance hybrid perovskite solar cells with polythiophene as hole-transporting layer via electrochemical polymerization , 2014 .

[14]  C. Brabec,et al.  A Universal Interface Layer Based on an Amine‐Functionalized Fullerene Derivative with Dual Functionality for Efficient Solution Processed Organic and Perovskite Solar Cells , 2015 .

[15]  Bo Qu,et al.  A hydrophobic hole transporting oligothiophene for planar perovskite solar cells with improved stability. , 2014, Chemical communications.

[16]  Juan Bisquert,et al.  Mechanism of carrier accumulation in perovskite thin-absorber solar cells , 2013, Nature Communications.

[17]  Chang-Lyoul Lee,et al.  Highly efficient and stable planar perovskite solar cells with reduced graphene oxide nanosheets as electrode interlayer , 2015 .

[18]  Juan Bisquert,et al.  Low-temperature processed electron collection layers of graphene/TiO2 nanocomposites in thin film perovskite solar cells. , 2013, Nano letters.

[19]  Anders Hagfeldt,et al.  Effect of Different Hole Transport Materials on Recombination in CH3NH3PbI3 Perovskite-Sensitized Mesoscopic Solar Cells. , 2013, The journal of physical chemistry letters.

[20]  Alan J. Heeger,et al.  Intensity dependence of current-voltage characteristics and recombination in high-efficiency solution-processed small-molecule solar cells. , 2013, ACS nano.

[21]  Young Chan Kim,et al.  o-Methoxy substituents in spiro-OMeTAD for efficient inorganic-organic hybrid perovskite solar cells. , 2014, Journal of the American Chemical Society.

[22]  J. Noh,et al.  Efficient inorganic–organic hybrid heterojunction solar cells containing perovskite compound and polymeric hole conductors , 2013, Nature Photonics.

[23]  Tzung-Fang Guo,et al.  CH3NH3PbI3 Perovskite/Fullerene Planar‐Heterojunction Hybrid Solar Cells , 2013, Advanced materials.