Subtle side chain modification of triphenylamine‐based polymer hole‐transport layer materials produces efficient and stable inverted perovskite solar cells

Abstract

Polymer hole-transport layers (HTLs) are critical components of inverted perovskite solar cells (IPVSCs). Triphenylamine derivatives PTAA (poly[bis (4-phenyl)(2,4,6-trimethylphenyl)amine]) and Poly-TPD (poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine]) have been widely adopted as hole-transport materials due to their perovskite passivation effects and suitable energy levels. However, the passivation mechanism (i.e., the functional group responsible for perovskite passivation) of triphenylamine derivative polymers remains unclear, hindering the development and application of this polymer type. Here, we develop a novel Poly-TPD derivative, S-Poly-TPD, by replacing the n-butyl functional group of Poly-TPD with an isobutyl group to explore the influence of alkyl groups on HTL performance and top-deposited perovskite properties. Compared with Poly-TPD, the increased CH 3 -terminal unit density and the decreased spatial distance between the -CH-CH 3 and -CH 2 -CH 3 units and the benzene ring in S-Poly-TPD not only enhanced the hole-transport ability but also improved the perovskite passivation effect, revealing for the first time the role of the alkyl groups in perovskite passivation. As a result, the S-Poly-TPD-based IPVSCs demonstrated high power-conversion efficiencies of 15.1% and 21.3% in

Hydrogel-based printing strategy for high-performance flexible thermoelectric generators

“…Except for the printability of hydrogel pastes, another focus is on the TE performance. Although numerous conductive polymers have been reported, 35,36 their TE properties are still low compared to inorganic semiconductor materials. 37 Among inorganic TE materials, 1D Te-based inorganic NRs exhibit excellent TE performance owing to the effect of “quantum well”, 9,38–40 which were employed in hydrogel pastes to achieve outstanding TE performance.…”

Influence of Component Properties on the Photovoltaic Performance of Monolithic Perovskite/Organic Tandem Solar Cells: Sub‐Cell, Interconnecting Layer, and Photovoltaic Parameters

“…Owing to the low thermal annealing temperature of the perovskite layer, organicinorganic mixed-halide WPSCs are compatible with all types (organic and inorganic) of charge-transport layer (CTLs) incorporated devices, and most of the reported high-performance organic-inorganic mixed-halide WPSCs adopted organic holetransport layer (HTL) based p-i-n type devices (Figure 1a). [21][22][23][24][25] In contrast, limited by the high thermal annealing temperature of the all-inorganic perovskite layer, all-inorganic WPSCs can only be spin-coated on metal-oxide ETLs (e.g., TiO 2 , SnO 2 , ZnO, and NiO x ). [26][27][28][29] Electron-transport layer (ETL, typically SnO 2 , TiO 2 , or ZnO)-based n-i-p type devices are typically more efficient than HTL (mainly NiO x )-based p-i-n type devices, owing to the optimized energy level alignments between the ETL and perovskite layer.…”

All‐Inorganic Perovskite‐Based Monolithic Perovskite/Organic Tandem Solar Cells with 23.21% Efficiency by Dual‐Interface Engineering

“…[1][2][3][4] In particular, POTSCs stand out in terms of semi-transparency and flexibility on top of the facile device integration stemming from naturally orthogonal active layers solutions, thus lending them a unique edge in next-generation smart and flexible photovoltaics. [5][6][7][8] However, the relatively low power conversion efficiency (PCE) stemming from the sub-optimized sub-cells is now their ″Achilles' heel.'' Recently, with the innovation of novel A-DA′D-A type small molecule acceptor materials such as Y6, Y6-Se, the rear narrow-bandgap organic sub-cells (SOSCs) have experienced a surge in PCE.…”