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The development of n-type conjugated polymers with superior thermoelectric properties remains a major challenge, primarily attributed to the limited availability of high-performance electron transport units. In this paper, two polymers, PBFDOTh-T and PBFDOTh-Se, are synthesized by introducing a 3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione (BFDO)-derived structural unit featuring quinone resonance properties. Due to the strong electron-deficient effect of the BFDO unit, both polymers exhibited low-lying lowest unoccupied molecular orbital (LUMO) energy levels, which enabled an efficient n-doping procedure. Additionally, the introduction of the quinone unit effectively facilitated carrier delocalization, and both polymers achieved high electrical conductivities after n-doping, with the highest conductivity of 8.6 S cm−1 obtained in the doped PBFDOTh-Se polymer. Detailed analysis revealed that the introduction of selenophene further enhanced the conjugated planarity of the polymer and reduced the structural disorder caused by doping, thus allowing a higher n-doping level and enabling simultaneous increases in conductivity and Seebeck coefficient. Finally, PBFDOTh-Se showed the highest power factor (PF) of 22.7 μW m−1 K−2. This work provides a way to construct high-performance n-type quinone polymers for thermoelectrics and offers insights into the relationship between polymer structure and thermoelectric properties. [ABSTRACT FROM AUTHOR]

The synthesis of multicomponent metal halide perovskites (MHPs) by cationic and/or halide alloying allows band gap tuning, optimizing performance and improving stability. However, these multicomponent materials often suffer from compositional, structural, and property inhomogeneities, leading to uneven carrier transport and significant non‐radiative recombination losses in lead halide perovskites. While many researchers have focused on the aggregation of perovskite halide ions, the impact of the surface potential has received relatively less attention. In this study, the multifunctional ionic liquid 1‐allyl‐3‐methylimidazole dicyanamide (AMI) is introduced into the perovskite precursor to effectively regulate the surface potential of the perovskite layer. This approach inhibits non‐radiative recombination, enhances carrier injection, and improves device performance. Surface potential homogenization within the perovskite layer leads to simultaneous improvements in both the efficiency and stability of perovskite solar cells. For wide‐bandgap perovskites (1.81 eV), the optimal power conversion efficiency (PCE) reaches 20.44%, with an open‐circuit voltage (Voc) of 1.339 V, a short‐circuit current density (Jsc) of 17.92 mA cm−2, and a high fill factor (FF) of 85%. This strategy also proved effective for conventional bandgap perovskite solar cells (PSCs) (1.53 eV), leading to a significant increase in performance, with the PCE increasing from 23.22% to 25.41%. [ABSTRACT FROM AUTHOR]

The optoelectronic properties and photovoltaic performance of nonfullerene electron acceptors (NFEAs) in organic solar cells (OSCs) are greatly influenced by the rational structure regulation of the central core unit. This study introduces a novel type of six‐membered fused electron‐donating core containing B─N covalent bonds to construct acceptor–donor–acceptor (A–D–A)‐type NFEAs. By modulating the branching alkyl chains on the nitrogen atom, two NFEAs, BN910 and BN1014, are synthesized and characterized. Both molecules exhibit strong near‐infrared absorption, narrow bandgaps (≈1.45 eV), appropriate energy levels, and tunable molecular packing behaviors, positioning them as promising candidates for efficient NFEAs in OSCs. The investigation reveals that BN1014, with longer and C2‐branched alkyl chains, demonstrates superior intermolecular packing and morphology within active layers, leading to enhanced exciton dissociation, improved charge transfer, and reduced charge recombination in OSCs. As a result, a power conversion efficiency (PCE) of 10.02% is achieved for D18:BN1014‐based binary OSCs. Notably, BN1014 can be utilized as the third component in the D18:DT‐Y6 binary system to fabricate the ternary OSCs, and a PCE of 17.65% is achieved, outperforming 17.05% of D18:DT‐Y6‐based binary OSCs. These findings highlight the potential of heteroarenes featuring B─N covalent bonds for constructing high‐efficiency NFEAs in OSCs. [ABSTRACT FROM AUTHOR]

The performance of organic photodetectors (OPDs) sensitive to the short-wavelength infrared (SWIR) light lags behind commercial indium gallium arsenide (InGaAs) photodetectors primarily due to the scarcity of organic semiconductors with efficient photoelectric responses exceeding 1.3 µm. Limited by the Energy-gap law, ultralow-bandgap organic semiconductors usually suffer from severe non-radiative transitions, resulting in low external quantum efficiency (EQE). Herein, a difluoro-substituted quinoid terminal group (QC-2F) with exceptionally strong electron-negativity is developed for constructing a new non-fullerene acceptor (NFA), Y-QC4F with an ultralow bandgap of 0.83 eV. This subtle structural modification significantly enhances intermolecular packing order and density, enabling an absorption onset up to 1.5 µm while suppressing non-radiation recombination in Y-QC4F films. SWIR OPDs based on Y-QC4F achieve an impressive detectivity (D*) over 10 11 Jones from 0.4 to 1.5 µm under 0 V bias, with a maximum of 1.68 × 10 12 Jones at 1.16 µm. Furthermore, the resulting OPDs demonstrate competitive performance with commercial photodetectors for high-quality SWIR imaging even under 1.4 µm irradiation., (© 2024 Wiley‐VCH GmbH.)