Dopant-free F-substituted benzodithiophene copolymer hole-transporting materials for efficient and stable perovskite solar cells

Abstract

Perovskite solar cells based on dopant-free PBDT[2F]T have achieved a power conversion efficiency (17.52%), combined with an impressive stability in contrast to that with the doped spiro-OMeTAD as a HTM in ambient atmosphere and even in high humidity.

Structurally‐tuned benzo[1,2‐b:4,5:b']dithiophene‐based polymer as a dopant‐free hole transport material for perovskite solar cells

“…Furthermore, when extracted from the time‐resolved PL spectra by fitting with bi‐exponential function (Figure 4B), the carrier lifetime of photo‐generated charges in the perovskite with Py1 HTM was much prolonged as compared with those in the perovskite with Py0 and Py4 HTMs (Table S1). These results implies that Py1 HTM with the appropriate combination of thienyl and pyridyl units is able to effectively reduce the non‐radiative recombination in PSCs by passivating the interface at perovskite/HTM 27,47,48 . We further confirmed this interfacial interaction and passivation tendency between HTMs and perovskite by performing XPS analysis.…”

“…For example, Xinqi Li et al have recently achieved highly efficient and stable PSCs by employing BDT‐based dopant‐free HTMs and adding polymer donor materials into anti‐solvent 21 . Hence, side chain tuning and electron donor‐electron acceptor (D‐A) alternating copolymerization have been attempted to optimize the energy levels, morphologies, and charge extraction/transport abilities of BDT‐based polymeric HTMs, which is required for the efficient delivering of photo generated carriers from perovskite absorber to anode 22–28 . However, the complicated and additional synthesis steps for these approaches have still prevented the further optimization and the commercialization of BDT‐based polymeric HTMs for high performance PSCs.…”

Highly Reproducible Fabrication of Perovskite Films with an Ultrawide Antisolvent Dripping Window for Large‐Scale Flexible Solar Cells

“…Preparation of Colloidal SnO 2 Nanocrystals Solution: SnO 2 NCs solution was prepared by our previous method. [32] Typically, SnCl 2 •2H 2 O solution (0.1 M) was prepared by dissolving SnCl 2 •2H 2 O separately in ethanol, isopropanol, butanol, and butanol containing certain content of water in a flask. Then, the solution was separately stirred at room temperature for 10 min.…”

Simple Yet Efficient: Arylamine‐Terminated Carbazole Donors for Organic Hole Transporting Materials

“…Hole transport materials (HTMs) are necessary for PSCs to extract and transport the free photogenerated holes within the perovskite material. Efforts have been devoted to designing and fabricating HTMs from organic building blocks, [ 5,6 ] including organic small molecules, [ 7–36 ] polymers, [ 37,38 ] and organometallic compounds. [ 39–41 ] Among them small organic HTMs have received tremendous attentions due to their high performance, structural variety, and easy fabrication.…”