A Two‐Dimensional Hole‐Transporting Material for High‐Performance Perovskite Solar Cells with 20 % Average Efficiency

Abstract

A readily available small molecular hole-transporting material (HTM), OMe-TATPyr, was synthesized and tested in perovskite solar cells (PSCs). OMe-TATPyr is a two-dimensional π-conjugated molecule with a pyrene core and four phenyl-thiophene bridged triarylamine groups. It can be readily synthesized in gram scale with a low lab cost of around US$ 50 g . The incorporation of the phenyl-thiophene units in OMe-TATPyr are beneficial for not only carrier transportation through improved charge delocalization and intermolecular stacking, but also potential trap passivation via Pb-S interaction as supported by depth-profiling XPS, photoluminescence, and electrochemical impedance analysis. As a result, an impressive best power conversion efficiency (PCE) of up to 20.6 % and an average PCE of 20.0 % with good stability has been achieved for mixed-cation PSCs with OMe-TATPyr with an area of 0.09 cm . A device with an area of 1.08 cm based on OMe-TATPyr demonstrates a PCE of 17.3 %.

Dopant‐Free Small‐Molecule Hole‐Transporting Material for Inverted Perovskite Solar Cells with Efficiency Exceeding 21%

“…Second, bis(4‐methoxyphenyl)amine has been identified as the preferential hole‐transporting moiety to improve charge mobility at molecular level due to its easy oxidizability and its ability to effectively transport positive charge. Also, the pseudo‐3D conjugated architecture of triphenylamine building block may endow molecules with isotropic charge transport property . Third, reinforced intermolecular interactions and π–π stacking are expected to result in high conductivity, which could be achieved by employing planar building blocks widely used in organic field‐effect transistors or thermoelectrics, such as thiophene‐based derivatives .…”

Dithieno[3,2‐b:2′,3′‐d]pyrrole Cored p‐Type Semiconductors Enabling 20 % Efficiency Dopant‐Free Perovskite Solar Cells

“…[10] TheH OMOs are delocalized throughout both TPAa nd DTP/thiophene,w hile the LUMOs are primarily localized on DTP/thiophene units.The E HOMO /E LUMO values are calculated to be À4.25/À4.12 eV for both molecules.T of urther visualize the electron density distribution in DTP-semiconductors,w ep erformed the electrostatic potential (ESP) analysis from DFT calculation. [9,12] On the other hand, the electron-deficient area (positive area) is spread out over the side TPAmoieties and the substituents on Na tom. [11] As such, the Pd 2+ ···S interactions are expected to be simultaneously constructed to passivate the surface defects of perovskite.…”

“…[11] As such, the Pd 2+ ···S interactions are expected to be simultaneously constructed to passivate the surface defects of perovskite. [9,12] On the other hand, the electron-deficient area (positive area) is spread out over the side TPAmoieties and the substituents on Na tom.…”

A Rutile TiO2 Electron Transport Layer for the Enhancement of Charge Collection for Efficient Perovskite Solar Cells

“…[1][2][3][4] In the past years,P SCs have become one of the most promising candidates in solar cells, [5][6][7][8] because of its low cost and high power conversion efficiency( PCE). [1][2][3][4] In the past years,P SCs have become one of the most promising candidates in solar cells, [5][6][7][8] because of its low cost and high power conversion efficiency( PCE).…”

“…Organic-inorganic hybrid lead halide perovskite solar cells (PSCs) are derived from dye-sensitized solar cells (DSSCs). [1][2][3][4] In the past years,P SCs have become one of the most promising candidates in solar cells, [5][6][7][8] because of its low cost and high power conversion efficiency( PCE). [9,10] Among many factors affecting the performance of PSCs,t he interface between the electron transport layer (ETL) and perovskite layer has attracted much attention owing to its significant role in electron collection, thus determining PSC performance.…”