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Organic photovoltaic (OPV) technology has recently achieved remarkable progress in academia, attaining power conversion efficiencies exceeding 19%, a breakthrough previously unimaginable. Despite these advancements, the translation of high‐efficiency OPV cells into the commercialization of OPV modules has been limited, impeding the market penetration of OPV technology. Upon careful examination, various challenges emerge, including disparities between laboratory research and industrial production in device architecture, influenced by considerations of cost and manufacturability. Additionally, the incorporation of high‐efficiency materials requires careful consideration not only of the compatibility between the photoactive layer and interface layers or transparent electrodes but also of the associated synthetic complexity of chemical structures and cost implications. While these issues are crucial, they may not be widely discussed in current mainstream research. In this article, the purpose is to identify bottlenecks from a material techniques perspective, with the aim of promoting increased resources in the research of pertinent module technologies. This effort is intended to propel OPV technology toward greater success and bring it into closer alignment with the goals of commercialization. [ABSTRACT FROM AUTHOR]

Organic photodetectors (OPDs) with spectral response extending from ultraviolet to near‐infrared domains are of great interest for many applications. Morphological impact on the performance of photomultiplication (PM)‐type OPDs, however, is still rarely investigated so far. Herein, a non‐fullerene acceptor, Y6‐Se‐HD, is synthesized, in which heavier selenium atoms substitute the sulfur atoms in the core of Y6, and used for fabricating PM‐OPDs. The resulting devices exhibit remarkable PM effects in a very broadband spectral range covering from 320 to 1090 nm. A maximum EQE value of ≈6500% at 860 nm is achieved at a low bias of −1.0 V. As compared with the device prepared with Y6 molecules, the Y6‐Se‐HD OPDs exhibited much enhanced performance. From the morphological analysis, we infer that Y6‐Se‐HD almost covers the entire active layer and avoids the direct contact of the hole‐trapping donor polymers with the Ag electrode, thereby resulting in stronger charge trapping and preventing possible charge recombination and/or quenching. Furthermore, finer phase separation between the donor and acceptor molecules also facilitates hole trapping and strengthens the PM effects. This research highlights the importance of morphological effects on the PM‐OPDs and demonstrates one approach for controlling the device morphology. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) and shortwave infrared (SWIR) image technologies are of interest for many emerging applications. Among photodetector technologies, organic photodetectors (OPDs) are groundbreaking light sensors with unique photon‐to‐electron responses at various wavelengths that offer limitless flexibility in field applications due to the tunable design of organic semiconductors. Herein, a top‐illuminated OPD deposited on bottom aluminum electrode with a spectral response beyond a wavelength of 1000 nm is reported, which suggests a feasibility for image sensors integrated with bottom readout circuit. The results reveal that a device composed of aluminum‐doped zinc oxide, nickel oxide, and indium‐doped zinc oxide as hole blocking layer, hole transporting layer, and transparent top electrode, respectively, shows the best performance at a wavelength of ≈1000 nm, achieving an outstanding external quantum efficiency of 74% with a responsivity of 0.64 A W−1 and a detectivity of 6.6 × 1012 Jones. The device also performs a fast photocurrent response time of 9.8 µs and a linear dynamic range of 98 dB. To the best of knowledge, this device performance is one of the best reported to date for NIR and SWIR OPDs. The values are also comparable to commercially available inorganic photodetectors. [ABSTRACT FROM AUTHOR]

Shortwave infrared (SWIR) image sensors have unique functions in many optical applications, leading to widespread attention in developing next‐generation materials and photodetector technologies. Organic photodetectors (OPDs) are highly promising due to their flexibility in molecular design and processability. However, integrating OPDs with silicon readout integrated circuits (ROICs) poses numerous challenges, often resulting in underestimated device performance and limiting technological progress. To address the requirements of integrating top‐illuminated OPD with ROICs and to enhance the external quantum efficiency (EQE), optical microcavities are introduced into the OPDs. The EQE in the SWIR region can be effectively enhanced by properly adjusting the thicknesses of the photoactive layer (PAL) and interlayers. Simulations of the optical field distribution further support the active functions of the microcavity structure. The spatial variation of the microcavities allows the spectral response to shift from 1000 to 1400 nm, and the optimized device achieves an EQE of 25.8% at 1260 nm. Finally, the OPDs are integrated with a silicon‐based test kit, and the results reveal comparable sensing performance, demonstrating the high potential of microcavity resonance for device integration. This design effectively improves the integration of OPDs with traditional ROICs and advances SWIR‐based organic image sensor technology further toward commercialization. [ABSTRACT FROM AUTHOR]

We propose the novel σ-π conjugated polymer poly(biphenyl germanium) grafted with two electron-donating acridan moieties on the Ge atom for use as the host material in a polymer light-emitting diode (PLED) with the sky-blue-emitting thermally activated delayed fluorescence (TADF) material DMAC-TRZ as the guest. Its high triplet energy (E T ) of 2.86 eV is significantly higher than those of conventional π-π conjugated polymers (E T =2.65 eV as the limit) and this guest emitter (E T =2.77 eV). The TADF emitter emits bluer emission than in other host materials owing to the low orientation polarizability of the germanium-based polymer host. The Ge atom also provides an external heavy-atom effect, which increases the rate of reverse intersystem crossing in this TADF guest, so that more triplet excitons are harvested for light emission. The sky-blue TADF electroluminescence with this host/guest pair gave a record-high external quantum efficiency of 24.1 % at maximum and 22.8 % at 500 cd m -2 ., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)