skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: Evaluation of the Passivation Effects of PEDOT:PSS on Inverted Perovskite Solar Cells
Abstract Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is a popular hole transport material in perovskite solar cells (PSCs). However, the devices with PEDOT:PSS exhibit large open‐circuit voltage (Voc) loss and low efficiency, which is attributed to mismatched energy level alignment and the poor interface of PEDOT:PSS and perovskite. Here, three polymer analogues to polyaniline (PANI), PANI–carbazole (P1), PANI–phenoxazine (P2), and PANI–phenothiazine (P3) are designed with different energy levels to modify the interface between PEDOT:PSS and the perovskite layer and improve the device performance. The effects of the polymers on the device performance are demonstrated by evaluating the work function adjustment, perovskite growth control, and interface modification in MAPbI3‐based PSCs. Low bandgap Sn–Pb‐based PSCs are also fabricated to confirm the effects of the polymers. Three effects are evaluated through the comparison study of PEDOT:PSS‐based organic solar cells and MAPbI3 PSCs based on the PEDOT:PSS modified by P1, P2, and P3. The order of contribution for the three effects is work function adjustment > surface modification > perovskite growth control. MAPbI3 PSCs modified with P2 exhibit a highVocof 1.13 V and a high‐power conversion efficiency of 21.06%. This work provides the fundamental understanding of the interface passivation effects for PEDOT:PSS‐based optoelectronic devices.  more » « less
Award ID(s):
1900047 1945503 1757220
PAR ID:
10384631
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Energy Materials
Volume:
12
Issue:
46
ISSN:
1614-6832
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; ; ; ; et al (, Angewandte Chemie International Edition)
    Abstract Surface passivation of perovskite solar cells (PSCs) using a low‐cost industrial organic pigment quinacridone (QA) is presented. The procedure involves solution processing a soluble derivative of QA,N,N‐bis(tert‐butyloxycarbonyl)‐quinacridone (TBOC‐QA), followed by thermal annealing to convert TBOC‐QA into insoluble QA. With halide perovskite thin films coated by QA, PSCs based on methylammonium lead iodide (MAPbI3) showed significantly improved performance with remarkable stability. A PCE of 21.1 % was achieved, which is much higher than 18.9 % recorded for the unmodified devices. The QA coating with exceptional insolubility and hydrophobicity also led to greatly enhanced contact angle from 35.6° for the pristine MAPbI3thin films to 77.2° for QA coated MAPbI3thin films. The stability of QA passivated MAPbI3perovskite thin films and PSCs were significantly enhanced, retaining about 90 % of the initial efficiencies after more than 1000 hours storage under ambient conditions. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; ; et al (, Small)
    Abstract Dimethylammonium lead iodide (DMAPbIx) has the potential to address the phase stability issue of inorganic perovskite solar cells (PSCs). In this study, the crystallinity, phase structure, defect states, and crystal growth habits of DMAPbIxare controlled by adjusting thexvalue during synthesis, where N,N‐dimethylacetamide (DMAC) is used as the solvent to regulate perovskite film growth. Furthermore, large‐area CsPbI2.85Br0.15perovskite films with preferred oriented growth are achieved using the optimizedxvalue in DMAPbIxthrough the slot‐die coating method. The inorganic PSCs, with a n‐i‐p structure and the active area of 0.04 cm2, achieve a champion power conversion efficiency (PCE) of 19.82%, with an open‐circuit voltage (Voc) of 1.16 V based on perovskite films formed by slot‐die coating. This work provides important insights into the DMAPbIx‐based method for fabricating high‐quality inorganic perovskite films, and paves the way for large‐area inorganic PSCs fabrication for practical applications. 
    more » « less
  3. ; ; ; ; ; ; ; ; ; ; et al (, Advanced Energy Materials)
    Abstract The optimal selection of alkyl chains and halogen ions in ammonium salts for addressing specific defect types in perovskite films remains unclear, although ammonium salts emerged as a promising strategy to enhance the performance of perovskite solar cells (PSCs). Herein, four ammonium salts are introduced with different alkyl chain types and halogen ions to passivate perovskite films. Branched‐alkyl chain ammonium salts exhibited superior passivation effects compared to linear‐alkyl chain salts, with the alkyl chain structure having a more significant impact on device performance than the halogen ion component. In addition, DFT calculations are performed to investigate which defect types in perovskite films are most effectively passivated by different alkyl chain types and halogen ions in ammonium salts. Branched‐alkyl chain ammonium salts demonstrated superior passivation effects on VPband VFAdefects in perovskite films compared to linear‐alkyl chain salts, while exhibiting similar passivation effects for VIdefects. PSCs passivated with tert‐OAI achieved an impressive efficiency of 25.49%, with a Vocof 1.19 V, a Jscof 25.40 mA cm−2, and an FF of 84.34%. This work highlights a targeted ammonium salt passivation strategy tailored to address different defect types in perovskite films, accounting for variations in perovskite composition and fabrication environments. 
    more » « less
  4. ; ; ; ; ; ; ; ; (, Journal of Materials Chemistry A)
    Conjugated molecules have been typically utilized as either hole or electron extraction layers to boost the device performance of perovskite solar cells (PSCs), formed from three-dimensional (3D) perovskites, due to their high charge carrier mobility and electrical conductivity. However, the passivating role of conjugated molecules in creating two-dimensional (2D) perovskites has rarely been reported. In this study, we report novel conjugated aniline 3-phenyl-2-propen-1-amine (PPA) based 2D perovskites and further demonstrate efficient and stable PSCs containing a (PPA) x (MAPbI 3 ) 1− x /MAPbI 3 bilayer thin film (where MA is CH 3 NH 3 + ). The (PPA) x (MAPbI 3 ) 1− x /MAPbI 3 bilayer thin film possesses superior crystallinity and passivated trap states, resulting in enhanced charge transport and suppressed charge carrier recombination compared to those of a 3D MAPbI 3 thin film. As a result, PSCs containing the (PPA) x (MAPbI 3 ) 1− x /MAPbI 3 bilayer thin film exhibit a power conversion efficiency (PCE) of 21.98%, which is approximately a 25% enhancement compared to that of the MAPbI 3 thin film. Moreover, un-encapsulated PSCs containing the (PPA) x (MAPbI 3 ) 1− x /MAPbI 3 bilayer thin film retain 50% of their initial PCE after 1200 hours in an ambient atmosphere (25 °C, and 30 ± 10 humidity), whereas PSCs with the 3D MAPbI 3 thin film show significant degradation after 100 hours and a degradation of more than 50% of their original PCE after 500 hours. These results demonstrate that the incorporation of conjugated molecules as organic spacer cations to create 2D perovskites on top of 3D perovskites is an effective way to approach high-performance PSCs. 
    more » « less
  5. ; ; ; ; ; ; ; ; (, RSC Advances)
    Perovskite solar cells have been rapidly developed in the past ten years. It was demonstrated that the interfacial layer plays an important role in device performance of perovskite solar cells. In this study, we report utilization of a photoinitiation-crosslinked zwitterionic polymer, namely dextran with carboxybetaine modified by methacrylate (Dex-CB-MA), as an interfacial layer to improve the film morphology of the CH 3 NH 3 PbI 3 photoactive layer and the interfacial contact between the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) hole extraction layer and CH 3 NH 3 PbI 3 photoactive layer. It is found that the Dex-CB-MA thin layer forms a better band alignment between the PEDOT:PSS hole extraction layer and CH 3 NH 3 PbI 3 photoactive layer, and improves the crystallization of the CH 3 NH 3 PbI 3 photoactive layer, resulting in efficient charge carrier transport. As a result, perovskite solar cells with the PEDOT:PSS/Dex-CB-MA hole extraction layer exhibit more than 30% enhancement in efficiency and dramatically boosted stability as compared with that with the PEDOT:PSS hole extraction layer. Our studies provide an effective and facile way to fabricate stable perovskite solar cells with high power conversion efficiency. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email