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Developing an artificial visual sensory system requires optoelectronic materials and devices that can mimic the behavior of biological synapses. Organic/polymeric semiconductors have emerged as promising candidates for optoelectronic synapses due to their tunable optoelectronic properties, mechanic flexibility, and biological compatibility. In this review, we discuss the recent progress in organic optoelectronic synaptic materials and devices, including their design principles, working mechanisms, and applications. We also highlight the challenges and opportunities in this field and provide insights into potential applications of these materials and devices in next‐generation artificial visual systems. By leveraging the advances in organic optoelectronic materials and devices, we can envision its future development in artificial intelligence. [ABSTRACT FROM AUTHOR]

Developing an artificial visual sensory system requires optoelectronic materials and devices that can mimic the behavior of biological synapses. Organic/polymeric semiconductors have emerged as promising candidates for optoelectronic synapses due to their tunable optoelectronic properties, mechanic flexibility, and biological compatibility. In this review, we discuss the recent progress in organic optoelectronic synaptic materials and devices, including their design principles, working mechanisms, and applications. We also highlight the challenges and opportunities in this field and provide insights into potential applications of these materials and devices in next‐generation artificial visual systems. By leveraging the advances in organic optoelectronic materials and devices, we can envision its future development in artificial intelligence. [ABSTRACT FROM AUTHOR]

• Understand public perception of AVs by analyzing social media data in China; • Introduce text network analysis to the research on public perception of AVs as a supplement to existing research methods; • Analyze the gender differences in public perception of AVs using social media; • The public's insufficient knowledge of AVs is related to the publicity of automobile companies and the media; • The public expresses more blame for vehicles with L2 driving automation than human drivers after the NIO crash. In China, vehicles with L2 driving automation are already widespread, while L3-L5 automated vehicles (AVs) are not allowed on the road. Surprisingly, crashes involving vehicles with L2 driving automation contributed to the public's discussion of L3-L5 AVs. Understanding the variations in public perception of AVs is imperative, which could significantly affect the future evolution of AVs. Respondents have few opportunities to express their views freely in survey-based studies relying on structured questionnaires (e.g., Likert scale). We collected 42,111 comments from Chinese mainstream social media platforms (Sina Weibo and Tik Tok) in August 2021 and applied advanced text mining technology (Latent Dirichlet Allocation topic model, text network analysis, and sentiment analysis) to understand variations in public perception of AVs before and after the crashes. The results show that the public expresses more blame for vehicles with L2 driving automation than human drivers and has misunderstandings about the current development of L3-L5 AVs, which is closely connected with publicity from automobile companies and media. Women were more negative than men both before and after the crash, and the sentiment difference was most significant in the first three days of the crash. This research provides new ideas for a timely understanding of the public perception of AVs. Findings contribute to specific policy recommendations to help in the technological change and wider adoption of AVs. [ABSTRACT FROM AUTHOR]

The development of semitransparent organic solar cells (ST‐OSCs) represents a significant step toward the commercialization of OSCs. However, the trade‐off between power conversion efficiency (PCE) and average visible transmittance (AVT) restricts further improvements of ST‐OSCs. Herein, it is demonstrated that a fibril network strategy can enable ST‐OSCs with a high PCE and AVT simultaneously. A wide‐bandgap polymer PBT1‐C‐2Cl that can self‐assemble into a fibril nanostructure is used as the donor and a near‐infrared small molecule Y6 is adopted as the acceptor. It is found that a tiny amount of PBT1‐C‐2Cl in the blend can form a high speed pathway for hole transport due to the well distributed fibril nanostructure, which increases the transmittance in the visible region. Meanwhile, the acceptor Y6 guarantees sufficient light absorption. Using this strategy, the optimized ST‐OSCs yield a high PCE of 9.1% with an AVT of over 40% and significant light utilization efficiency of 3.65% at donor/acceptor ratio of 0.25:1. This work demonstrates a simple and effective approach to realizing high PCE and AVT of ST‐OSCs simultaneously. [ABSTRACT FROM AUTHOR]

• Study conducted a randomized controlled trial and applied Double Machine Learning. • The causality between "over-hype" and public misconceptions about AVs was identified. • Participants believed AVs are already available but not safer than human drivers. • The sociodemographic factors have little impact on the susceptibility to "over-hype." • It is necessary to regulate public communication about AVs. Traffic accidents caused by drivers' over-reliance on SAE L2 advanced driver assistance systems (ADAS) have become a new type of accident worthy of attention. There is growing concern that the "over-hype" about automation technology produced by manufacturers or the media might affect the formation of public misconceptions about autonomous vehicles (AVs), further influencing their unsafe interaction behaviors with the system. The purpose of our study was to explore whether and how "over-hype" in various contexts affects public misconceptions about AVs from the view of causality. We conducted a randomized controlled trial with a control group of 396 participants and a treatment group of 545 participants drawn from Zhenjiang, China. We applied Double Machine Learning (DML), ordered logit models, and significant difference tests to estimate the impact of "over-hype" in various contexts. The results found that the statement that "over-hype" caused public misconceptions was less rigorous. Significant causality varies among contexts of "over-hype" and aspects of misconceptions. Specifically, "over-hype" in fatal accident reports will lead to availability misconception about AVs, but not safety misconception, suggesting that participants believed AVs were available nowadays but not safe as human drivers. "Over-hype" that exaggerates ADAS capabilities has the greatest average treatment effect on public misconceptions, especially the safety misconception. We found that the young and the more educated are more likely to have safety and availability misconceptions under the "over-hype" of some contexts. However, the effects of "over-hype" varied less among groups with different socio-economic factors on the whole, which revealed the universality of the influence of "over-hype." The results provided empirical evidence for regulating propaganda about AV technology and provided practical insights on how to introduce AV technology to the general public properly. [ABSTRACT FROM AUTHOR]

A pair of linear two-dimensional conjugated non-fullerene acceptors, named as TVIDTPDI and TVIDTzPDI , which have the same perylene diimide end-capping groups, but different in two-dimensional conjugated central core (the dithienyl vinylene-fused indacenodithiophene or dithienyl vinylene-fused indacenodithiazole), were successfully synthesized and evaluated as acceptor materials in organic solar cells (OSCs). Such core units in these small acceptors play a decisive role in the formation of the nanoscale separation of the blend films, which were systematically investigated through absorption spectra, electrochemical properties, density functional theory calculations, AFM images, and charge mobility measurement by space-charge-limited current SCLC method. By incorporation of the dithienyl vinylene-fused indacenodithiazole-based core, TVIDTzPDI showed better planarity in the core unit with a dihedral 45.4° and 49.6° angle of between central core and the PDI. Moreover, the TVIDTzPDI blend with PTB7-Th displays higher and more balanced mobilities ( μ h = 4.56 × 10 −4 and μ e = 6.12 × 10 −4 cm 2 V −1 s −1 ) in comparison with those of TVIDTPDI blend with PTB7-Th . Therefore, the TVIDTzPDI/PTB7-Th based OSCs showed a higher PCE of 2.09% than that of the TVIDTPDI/ PTB7-Th devices (1.50%). The purpose of this study is to provide a facile strategy to design PDI-based two-dimensional conjugated small molecular acceptors and understand the impact of installing the two dimensional core and more electron-deficient thiazole unit in such small molecular acceptors. [ABSTRACT FROM AUTHOR]

A twisted bay‐substituted tetraphenyl functionalized perylenediimide monomer (TP‐PDI) is synthesized. A high power conversion efficiency of 4.1% is achieved for organic solar cells incorporated a combination of TP‐PDI electron acceptor and PTB7‐Th electron donor, indicating that chemical modification of PDI monomers is a useful way of designing high‐performance non‐fullerene electron acceptors. [ABSTRACT FROM AUTHOR]

The structure of molecular aggregates is crucial for charge transport and photovoltaic performance in organic solar cells (OSCs). Herein, the intermolecular interactions and aggregated structures of nonfused‐ring electron acceptors (NFREAs) are precisely regulated through a halogen transposition strategy, resulting in a noteworthy transformation from a 2D‐layered structure to a 3D‐interconnected packing network. Based on the 3D electron transport pathway, the binary and ternary devices deliver outstanding power conversion efficiencies (PCEs) of 17.46 % and 18.24 %, respectively, marking the highest value for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

The structure of molecular aggregates is crucial for charge transport and photovoltaic performance in organic solar cells (OSCs). Herein, the intermolecular interactions and aggregated structures of nonfused‐ring electron acceptors (NFREAs) are precisely regulated through a halogen transposition strategy, resulting in a noteworthy transformation from a 2D‐layered structure to a 3D‐interconnected packing network. Based on the 3D electron transport pathway, the binary and ternary devices deliver outstanding power conversion efficiencies (PCEs) of 17.46 % and 18.24 %, respectively, marking the highest value for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

The human visual system to process real‐time light signals and safeguard against excessive light exposure serves as a model for artificial vision systems. Despite the wide use of optoelectronic synaptic devices in such simulations, their complex circuitry and high energy consumption have impeded further development. Herein, a biomimetic ocular system utilizing organic all‐photonic synapses is constructed to realize sensation, memory, processing, and protective light reflex abilities. The synaptic performances are facially regulated by simple molecular engineering to afford a record PPF value of 430%. Impressively, a large area (400 cm2) synaptic device with a high uniformity (96%) exhibited four fundamental functions of an ocular system for the first time, which significantly simplified the circuit system and reduced energy consumption. This work provides a facial strategy to construct all‐photonic synapses, holding great potential in prosthetics and neurorobotics. [ABSTRACT FROM AUTHOR]

In the development of high‐performance organic solar cells (OSCs), the self‐organization of organic semiconductors plays a crucial role. This study focuses on the precisely manipulation of molecular assemble via tuning alkyl side‐chain topology in a series of low‐cost nonfused‐ring electron acceptors (NFREAs). Among the three NFREAs investigated, DPA‐4, which possesses an asymmetric alkyl side‐chain length, exhibits a tight packing in the crystal and high crystallinity in the film, contributing to improved electron mobility and favorable film morphology for DPA‐4. As a result, the OSC device based on DPA‐4 achieves an excellent power conversion efficiency of 16.67 %, ranking among the highest efficiencies for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

In the development of high‐performance organic solar cells (OSCs), the self‐organization of organic semiconductors plays a crucial role. This study focuses on the precisely manipulation of molecular assemble via tuning alkyl side‐chain topology in a series of low‐cost nonfused‐ring electron acceptors (NFREAs). Among the three NFREAs investigated, DPA‐4, which possesses an asymmetric alkyl side‐chain length, exhibits a tight packing in the crystal and high crystallinity in the film, contributing to improved electron mobility and favorable film morphology for DPA‐4. As a result, the OSC device based on DPA‐4 achieves an excellent power conversion efficiency of 16.67 %, ranking among the highest efficiencies for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing the asymmetric end‐group engineering, an asymmetric nonfused‐ring electron acceptor (NFREA) was designed and synthesized. Compared with the symmetric analogs (NoCA‐17 and NoCA‐18), NoCA‐19 possesses broader light absorption range, more coplanar π‐conjugated backbone, and appropriate crystallinity according to the experimental and theoretical results. The organic solar cells based on J52:NoCA‐19 exhibited a power conversion efficiency as high as 12.26%, which is much higher than those of J52:NoCA‐17 (9.50%) and J52:NoCA‐18 (11.77%), mainly due to more efficient exciton dissociation, better and balanced charge mobility, suppressed recombination loss, shorter charge extraction time, longer charge carrier lifetimes, and more favorable blend film morphology. These findings demonstrate the great potential of asymmetric end‐group engineering in exploring low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing thiazole and 4‐chlorothiazole as the A′ units, two A‐D‐A′‐D‐A type nonfused‐ring electron acceptors (NFREAs) Tz‐H and Tz‐Cl were designed and synthesized. Replacing thiazole in Tz‐H with 4‐chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz‐Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz‐H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

The power conversion efficiencies (PCEs) of all‐polymer solar cells (all‐PSCs) have already exceeded 17%. However, the limited absorption range of an all‐polymer system results in significantly reduced short‐circuit current density (Jsc), which eventually influences the PCE improvement. To broaden the light absorption of polymer acceptors, herein, benzotriazole is introduced in the core unit of small molecule acceptors and thus two narrow‐bandgap polymer acceptors named PTz‐BO and PTz‐C11 featuring the same molecular backbone and different side‐chain length are synthesized. Compared with PTz‐C11, the PTz‐BO based‐all PSCs deliver a slightly reduced Jsc, a large open‐circuit voltage (Voc) and a low voltage loss below 0.50 V. Moreover, ternary all‐PSCs are constructed by introducing PTz‐C11 as a guest component. Benefiting from the reduced recombination, improved exciton generation and dissociation, and balanced charge transport, a high efficiency of 16.58% is obtained for the ternary all‐PSCs, with a high Jsc over 25 mA cm−2 without sacrificing the Voc. Such result represents the highest efficiency reported for benzotriazole‐based all‐PSCs in the literature thus far. This work demonstrates the great potential of benzotriazole for the synthesis of efficient narrow‐bandgap polymer acceptors. [ABSTRACT FROM AUTHOR]

Side-chain engineering is one of the most promising ways to develop non-fullerene acceptors (NFAs) for organic solar cells. In this work, we designed and synthesized a novel acceptor IT-BnC6-4F by introducing methylene group between the phenyl group and the sp3 hybrid carbon atoms of central conjugated cores to form benzyl side chains. IT-BnC6-4F shows broader absorption spectrum and higher crystallinity than those of its analogue, IT-4F. When blended with PT2, the IT-BnC6-4F based device achieved a high power conversion efficiency (PCE) of 13.36 %, with an open-circuit voltage (V oc) of 0.87 V and a short-circuit current density (J sc) of 20.99 mA cm−2. [Display omitted] • Benzyl side chains functionalized non-fullerene acceptor was synthesized. • Substitution effects of the benzyl side chains on photovoltaic performance of the non-fullerene acceptor were investigated. • Benzyl side chains could endure the non-fullerene acceptor with broader absorption spectrum and higher crystallinity. [ABSTRACT FROM AUTHOR]

Morphological stability is crucially important for the long‐term stability of polymer solar cells (PSCs). Many high‐efficiency PSCs suffer from metastable morphology, resulting in severe device degradation. Here, a series of copolymers is developed by manipulating the content of chlorinated benzodithiophene‐4,8‐dione (T1‐Cl) via a random copolymerization approach. It is found that all the copolymers can self‐assemble into a fibril nanostructure in films. By altering the T1‐Cl content, the polymer crystallinity and fibril width can be effectively controlled. When blended with several nonfullerene acceptors, such as TTPTT‐4F, O‐INIC3, EH‐INIC3, and Y6, the optimized fibril interpenetrating morphology can not only favor charge transport, but also inhibit the unfavorable molecular diffusion and aggregation in active layers, leading to excellent morphological stability. The work demonstrates the importance of optimization of fibril network morphology in realizing high‐efficiency and ambient‐stable PSCs, and also provides new insights into the effect of chemical structure on the fibril network morphology and photovoltaic performance of PSCs. [ABSTRACT FROM AUTHOR]

Perylenediimide (PDI)-based small molecules have significantly contributed to the development of non-fullerene acceptors, whereas the development of PDI-based polymer acceptors is relatively lagging behind. In this study, we designed and synthesized two PDI-based n-type polymers named as PF-PDI and PBDT-PDI, in which PDI was used as electron-deficient unit and fluorene (F) or benzodithiophene (BDT) were used as electronrich components. The density functional theory (DFT) calculations and grazing incidence wide-angle X-ray scattering (GIWAXS) results indicate that the PF-PDI shows larger steric hindrance and relatively weaker lamellar packing than that of PBDT-PDI. Comparing with PBDT-PDI, PF-PDI shows red-shift absorption and lower-lying HOMO level, which agrees well with the DFT results. A well-known wide bandgap polymer donor, PDBT-T1 was employed to fabricate polymer solar cells (PSCs) with the two acceptors. The all polymer solar cells (all-PSCs) based on PDBT-T1:PF-PDI showed a high power conversion efficiency (PCE) of 4.47%, which is approximately 2-fold larger than that of devices with PDBT-T1:PBDT-PDI (PCE = 2.70%). [ABSTRACT FROM AUTHOR]

Ternary structures are demonstrated as a promising approach to increase the efficiency and light harvesting of solar cells. A high power conversion efficiency of 10.2% is achieved for ternary organic solar cells with two efficient polymer donors. The improved performance is attributed to the synergistic effects of enhanced light absorption and charge transport, efficient energy transfer, improved charge generation and morphology. [ABSTRACT FROM AUTHOR]

Fluorination exhibits multiple effects on the photophysical properties of conjugated copolymers and has attracted enormous attention in organic solar cells (OSCs). Herein, a series of structurally identical benzo[1,2-c:4,5-c′]dithiophene-4,8-dione (T1) based polymers (named PPhF0-T1 to PPhF4-T1) with different numbers of fluorine substitutions have been designed and synthesized. With the number of fluorine substitution increases, the energy levels of the polymers decrease gradually. ITPTC non-fullerene acceptor was employed to fabricate OSCs with these polymers. We found that the introduction of fluorine can effectively improve the open-circuit voltage of the device. Upon one or two fluorine atoms are appended to the polymer, the corresponding short-circuit currents (J sc s) are obviously promoted. However, due to the excessive phase separation and hence suppressed charge carrier mobility, the J sc decreases when there are four fluorine atoms in the polymer. Consequently, without any additives, the PPhF2-T1 based device gives the highest power conversion efficiency of 10.61%, which is much higher than that of nonfluorinated polymer based OSC (3.97%). This work presents a systematic study upon the effect of different numbers of fluorine atoms on the photovoltaic performance of OSCs, which may serve as a useful guideline in the design of efficient conjugated polymers. To investigated the effect of fluorination on the performance of T1 copolymers. We designed and synthesized four copolymers by altering the numbers of fluorine atoms on the benzene group (named PPhF0-T1 to PPhF4-T1). When one or two F atoms are introduced to the polymers, the PCEs of OSCs are significantly improved. PPhF2-T1:ITCPTC based device delivers a highest PCE of 10.61%, while PPhF4-T1 based OSC yields a relatively lower PCE of 6.28%. Image 1 • Different numbers of fluorine substitutions controllable conjugated polymers were synthesized. • Substitution effects of amount of fluorine atoms on the photovoltaic performance were systematically investigated. • Multiple understanding the fluorination would be better for development of high-performance polymer donor materials. [ABSTRACT FROM AUTHOR]

Semitransparent organic solar cells (STOSCs) are ideal candidates for building‐integrated photovoltaics. Power conversion efficiency (PCE) is one of the most important parameters of STOSCs, which is typically limited by the intrinsic narrow absorption of thin active layer. Ternary structure is demonstrated as an efficient approach to broaden the light absorption and manipulate the morphology, thus leading to improved PCEs by introducing a third component into the binary system. However, STOSCs based on ternary systems are rarely studied. In this contribution, semitransparent ternary solar cells are fabricated using a wide‐bandgap (Eg = 2.10 eV) polymer donor, PBT1‐S, as the third component. It is found that the addition of a small amount of PBT1‐S to PTB7‐Th:PC71BM blend has a negligible influence on its average visible transmittance (AVT) and color perception. A PCE of 9.2% is achieved for the champion ternary device with 20% AVT, which is one of the highest values for STOSCs. The results indicate that ternary structure is a promising approach for the fabrication of high‐performance STOSCs. Semitransparent organic solar cells (STOSCs) based on ternary structure are rarely studied. Here, a high efficiency of 9.2% is achieved for the champion semitransparent ternary device with 20% average visible transmittance, which is among the highest power conversion efficiencies reported for STOSCs so far. This indicates that the ternary structure is a promising strategy to fabricate high‐performance STOSCs. [ABSTRACT FROM AUTHOR]