A Dopant-free hole transporting layer for efficient and stable planar perovskite solar cells

Tavakoli, M. M ; Sharif University of Technology | 2020

645 Viewed
  1. Type of Document: Article
  2. DOI: 10.1002/pssr.202000147
  3. Publisher: Wiley-VCH Verlag , 2020
  4. Abstract:
  5. Herein, a new dopant-free organic material, PV2000, as a stable hole transporting layer (HTL) for the fabrication of stable and efficient perovskite solar cells (PSCs) is introduced. For this purpose, planar PSCs using a triple-A cation perovskite composition are fabricated and the commonly used 2,2′,7,7′-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD) HTL is replaced by dopant-free PV2000 polymer. The characterization results disclose that the PV2000 has a great thermal stability, good hole mobility, and suitable band alignment that matches well with the valence band of triple-A cation perovskite. After proper optimization of PV2000 film thickness, a planar PSC with maximum power conversion efficiency (PCE) of 18.93% is achieved, which is comparable with the spiro-based device (19.62%). Moreover, the PCE of the PV2000-based device is further improved up to 20.5% using a band alignment engineering by deposition of thin layer of polyvinylpyrrolidone (PVP) at perovskite/HTL interface. More importantly, it is found that the thermal, moisture, and operational stabilities of the PSCs with PV2000 HTL are improved drastically compared with the spiro-based devices, where the PSC with PV2000 retains ≈88% of its initial PCE value under continuous illumination for 250 h compared with the spiro-based one (39%). © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
  6. Keywords:
  7. Device stability ; Hole transporting layer ; Power conversion efficiency ; PV2000 polymer ; Deposition ; Hole mobility ; Perovskite ; Positive ions ; Band alignments ; Dopant-free ; Hole transporting layers ; Maximum power ; Operational stability ; Organic materials ; Polyvinyl pyrrolidone ; Spirobifluorene ; Perovskite solar cells
  8. Source: Physica Status Solidi - Rapid Research Letters ; Volume 14, Issue 7 , 2020
  9. URL: https://onlinelibrary.wiley.com/doi/abs/10.1002/pssr.202000147