A Simple 3,4‐Ethylenedioxythiophene Based Hole‐Transporting Material for Perovskite Solar Cells

Abstract

We report a novel electron-rich molecule based on 3,4-ethylenedioxythiophene (H101). When used as the hole-transporting layer in a perovskite-based solar cell, the power-conversion efficiency reached 13.8 % under AM 1.5G solar simulation. This result is comparable with that obtained using the well-known hole transporting material 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD). This is the first heterocycle-containing material achieving >10 % efficiency in such devices, and has great potential to replace the expensive spiro-OMeTAD given its much simpler and cheaper synthesis.

High‐Efficiency Perovskite Solar Cells Using Molecularly Engineered, Thiophene‐Rich, Hole‐Transporting Materials: Influence of Alkyl Chain Length on Power Conversion Efficiency

“…[18][19][20][21][22][23][24][25][26] An alternative chemical approach for designing high efficient HTMs is based on polycyclic aromatics as a central core, such as pentacene, [27] triazatruxene, [28] thiolated nanographene [29] or benzotrithiophene, [30] endowed with arylamines derivatives. These -conjugated structures show excellent holetransporting properties due to the stacking of the planar structure through intramolecular - interactions, which lead to excellent power conversion efficiencies.…”

Over 20% PCE perovskite solar cells with superior stability achieved by novel and low-cost hole-transporting materials

“…25 However, apart from a few exceptions, 25,29 most PSCs based on thiophene HTMs show a PCE lower than 16%. [35][36][37][38][39][40][41][42] Herein, we report the synthesis and characterization as well as the application in perovskite solar cells of two novel thiophene-based HTMs, coded Z25 and Z26. The latter is derived by introdution of two double bonds into Z25 as shown in Figure 1a.…”

Benzotrithiophene‐Based Hole‐Transporting Materials for 18.2 % Perovskite Solar Cells

“…These interface layers play an important role for transporting and blocking the charges. A wide number of HTMs have been synthesized and investigated in combination with perovskite absorber ranging from classical semiconducting polymers to small molecules.Focusing on the latter, different central cores have been used in the state-of-the-art photovoltaic devices, such as 9,9'-spirobifluorene, [14] spiro-liked derivatives, [15] thiophene derivatives, [16] triphenylamine, [17] bridged-triphenylamines, [18,19] pyrene, [20] 3,4-ethylenedioxythiophene, [21] linear p-conjugated, [22][23][24] triptycene, [25] tetraphenylethene, [26] silolothiophene or triazines, [27] all of them namely decorated with diarylamines, triarylamines and/or carbazole derivatives. With this approach, the best power conversion efficiency obtained to date, up to 20 %, [13] has been achieved by using the polymer poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA).…”