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Minimizing energy loss is crucial for breaking through the efficiency bottleneck of organic solar cells (OSCs). The main mechanism of energy loss can be attributed to non-radiative recombination energy loss (ΔE nr ) that occurs due to exciton-vibration coupling. To tackle this challenge, tuning intramolecular noncovalent interactions is strategically utilized to tailor novel fused ring electron acceptors (FREAs). Upon comprehensive analysis of both theoretical and experimental results, this approach can effectively enhance molecular rigidity, suppress structural relaxation, reduce exciton reorganization energy, and weakens exciton-vibration coupling strength. Consequently, the binary OSC device based on Y-SeSe, which features dual strong intramolecular Se ⋅ ⋅ ⋅ O noncovalent interactions, achieves an outstanding power conversion efficiency (PCE) of 19.49 %, accompanied by an extremely small ΔE nr of 0.184 eV, much lower than those of Y-SS and Y-SSe based devices with weaker intramolecular noncovalent interactions. These achievements not only set an efficiency record for selenium-containing OSCs, but also mark the lowest reported ΔE nr value among high-performance binary devices. Furthermore, the ternary blend device showcases a remarkable PCE of 20.51 %, one of the highest PCEs for single-junction OSCs. This work demonstrates the effectiveness of intramolecular noncovalent interactions in suppressing exciton-vibration coupling, thereby achieving low-energy-loss and high-efficiency OSCs., (© 2024 Wiley-VCH GmbH.)

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., (© 2024 Wiley-VCH GmbH.)

High performance organic solar cells (OSCs) are usually realized by using post-treatment and/or additive, which can induce the formation of metastable morphology, leading to unfavorable device stability. In terms of the industrial production, the development of high efficiency as-cast OSCs is crucially important, but it remains a great challenge to obtain appropriate active layer morphology and high power conversion efficiency (PCE). Here, efficient as-cast OSCs are constructed via introducing a new polymer acceptor PY-TPT with a high dielectric constant into the D18:L8-BO blend to form a double-fibril network morphology. Besides, the incorporation of PY-TPT enables an enhanced dielectric constant and lower exciton binding energy of active layer. Therefore, efficient exciton dissociation and charge transport are realized in D18:L8-BO:PY-TPT-based device, affording a record-high PCE of 18.60% and excellent photostability in absence of post-treatment. Moreover, green solvent-processed devices, thick-film (300 nm) devices, and module (16.60 cm 2 ) are fabricated, which show PCEs of 17.45%, 17.54%, and 13.84%, respectively. This work brings new insight into the construction of efficient as-cast devices, pushing forward the practical application of OSCs., (© 2024 Wiley‐VCH GmbH.)

The design of high activity catalyst for the efficiently conversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) gains great interest. The rationally tailoring of electronic structure directly affects the interaction between catalysts and organic substrates, especially molecular oxygen as the oxidant. This work, the bimetallic catalysts AuPd/CeO 2 were prepared by the combining method of chemical reduction and photo-deposition, effectively concerting charge between Au and Pd and forming the electron-rich state of Au. The increasing of oxygen vacancy concentration of CeO 2 by acidic treatment can facilitate the adsorption of HMF for catalysts and enhance the yield of FDCA (99.0 %). Moreover, a series of experiment results combining with density functional theory calculation illustrated that the oxidation performance of catalyst in HMF conversion was strongly related to the electronic state of interfacial Au-Pd-CeO 2 . Furthermore, the electron-rich state sites strengthen the adsorption and activation of molecular oxygen, greatly promoting the elimination of β-hydride for the selective oxidation of 5-hydroxymethyl-2-furancarboxylic acid (HMFCA) to FDCA, accompanied with an outgoing FDCA formation rate of 13.21 mmol ⋅ g -1  ⋅ min -1 at 80 °C. The perception exhibited in this research could be benefit to understanding the effects of electronic state for interfacial sites and designing excellent catalysts for the oxidation of HMF., (© 2024 Wiley-VCH GmbH.)

The development of high-efficiency thickness-insensitive organic solar cells (OSCs) is crucially important for the mass production of solar panels. However, increasing the active layer thickness usually induces a substantial loss in efficiency. Herein, a ternary strategy in which an oligomer DY-TF is incorporated into PM6:L8-BO system as a guest component is adopted to break this dilemma. The S···F intramolecular noncovalent interactions in the backbone endow DY-TF with a high planarity. Upon the addition of DY-TF, the crystallinity of the blend is effectively improved, leading to increased charge carrier mobility, which is highly desirable in the fabrication of thick-film devices. As a result, thin-film PM6:L8-BO:DY-TF-based device (110 nm) shows a power conversion efficiency (PCE) of 19.13%. Impressively, when the active layer thickness increases to 300 nm, an efficiency of 18.23% (certified as 17.8%) is achieved, representing the highest efficiency reported for 300 nm thick OSCs thus far. Additionally, blade-coated thick device (300 nm) delivers a promising PCE of 17.38%. This work brings new insights into the construction of efficient OSCs with high thickness tolerance, showing great potential for roll-to-roll printing of large-area solar cells., (© 2023 Wiley-VCH GmbH.)

Photonic synapses with the dual function of optical signal detection and information processing can simulate human visual system. However, photonic synapses with selective detection of short-wavelength infrared (SWIR) light have never been reported, which can not only broaden the human vision region but also integrate neuromorphic computation and infrared optical communication. Here, organic photonic synapses based on a new donor-acceptor copolymer P1 are fabricated, which exhibit excellent synaptic characteristics with selective detection for SWIR and extremely low energy consumption (2.85 fJ). The working mechanism is rooted in energy level barriers and unbalanced charge transportation. Moreover, these photonic synapses demonstrate excellent performance in multi-signal logic editing, letter imaging and memory with noise reduction function. This contribution provides ideas of constructing selective-response synapses for artificial visual system and neuromorphic computing., (© 2022 Wiley-VCH GmbH.)

The large energy loss (E loss ) is one of the main obstacles to further improve the photovoltaic performance of organic solar cells (OSCs), which is closely related to the charge transfer (CT) state. Herein, ternary donor alloy strategy is used to precisely tune the energy of CT state (E CT ) and thus the E loss for boosting the efficiency of OSCs. The elevated E CT in the ternary OSCs reduce the energy loss for charge generation (ΔE CT ), and promote the hybridization between localized excitation state and CT state to reduce the nonradiative energy loss (ΔE nonrad ). Together with the optimal morphology, the ternary OSCs afford an impressive power conversion efficiency of 19.22% with a significantly improved open-circuit voltage (V oc ) of 0.910 V without sacrificing short-cicuit density (J sc ) and fill factor (FF) in comparison to the binary ones. This contribution reveals that precisely tuning the E CT via donor alloy strategy is an efficient way to minimize E loss and improve the photovoltaic performance of OSCs., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Upgrading furfuralcohols and furfurals to furancarboxylic acids is of great significance for high value-added downstream chemicals synthesis and biomass conversion. Developing an efficient catalyst is the key to acquiring a completely sustainable process. Herein, nitrogen-doped carbon-supported bimetallic AuPd bowl-like catalysts were synthesized. The surface wettability of nitrogen-doped carbon was well adjusted by the nitrification process. Benefiting from the alloying effect of bimetallic AuPd catalyst and the formation of hydroxyl radical initiated by H 2 O dissociation on the hydrophilic surface of nitrated nitrogen-doped carbon, base-free aerobic oxidation of 5-hydroxymethylfurfural (HMF) could produce the highest 2,5-furandicarboxylic acid (FDCA) yield of 93.9 %. In-situ infrared spectroscopy uncovered adsorption configuration of HMF, and the nitrated carbon surface was favorable for HMF and intermediates to enter the active sites, greatly promoting the catalytic oxidation process. Employing other furfuralcohols (furfuryl alcohol, furan-2,5-diyldimethanol, 2,5-bishydroxymethylfuran) as well as furfural and 5-methylfurfural as starting materials, 35.6-95.4 % yield of furancarboxylic acids (FDCA, 2-furoic acid, 5-methyl-2-furoic acid) were also obtained. Moreover, the developed catalysts could maintain excellent stability and activity after four successive runs. This deep insight into the role of bimetallic synergy and surface wettability provides a basis for the rational design of the highly efficient catalysts for the oxidation of furfuralcohols and furfurals and related reactions., (© 2022 Wiley-VCH GmbH.)

The innovation of high-performance fused-ring electron acceptors (FREAs) has carried the field of organic solar cells (OSCs) toward a new stage of development. However, due to high synthetic complexity and production costs, FREAs may not be the most promising candidates for future commercialization applications. To address these disadvantages of FREAs, a series of low-cost acceptors, named as noncovalently FREAs (NFREAs), is successfully constructed by employing the strategy of noncovalently conformational locks. Herein, a novel NFREA (BDTO-4F) based on 3,7-dialkyloxybenzo[1,2-b:4,5-b']dithiophene is synthesized and fully characterized. Benefiting from the complementary absorption of the donor and acceptor, balanced charge transport, and favorable film morphology, J52:BDTO-4F based OSCs afford a satisfied power conversion efficiency of 12.09%, much higher than PBDB-T:BDTO-4F-based devices (8.30%). It is worth mentioning that BDTO-4F possesses a higher figure-of-merit value of 55.65 in comparison with several representative FREAs based on a cost-efficiency evaluation. This work demonstrates the potential of the novel benzo[1,2-b:4,5-b″]dithiophene derivative for constructing low-cost and high-performance NFREAs, providing a valuable insight on the materials design., (© 2022 Wiley-VCH GmbH.)

The variation of the vertical component distribution can significantly influence the photovoltaic performance of organic solar cells (OSCs), mainly due to its impact on exciton dissociation and charge-carrier transport and recombination. Herein, binary devices are fabricated via sequential deposition (SD) of D18 and L8-BO materials in a two-step process. Upon independently regulating the spin-coating speeds of each layer deposition, the optimal SD device shows a record power conversion efficiency (PCE) of 19.05% for binary single-junction OSCs, much higher than that of the corresponding blend casting (BC) device (18.14%). Impressively, this strategy presents excellent universality in boosting the photovoltaic performance of SD devices, exemplified by several nonfullerene acceptor systems. The mechanism studies reveal that the SD device with preferred vertical components distribution possesses high crystallinity, efficient exciton splitting, low energy loss, and balanced charge transport, resulting in all-around enhancement of photovoltaic performances. This work provides a valuable approach for high-efficiency OSCs, shedding light on understanding the relationship between photovoltaic performance and vertical component distribution., (© 2022 Wiley-VCH GmbH.)

Developing an efficient catalyst to upgrade 5-hydroxymethylfurfural (HMF) to high-value-added downstream chemicals is of great significance in biomass conversion. Nanorod (110)-, nanocube (100)-, and nanooctaheron (111)-CeO 2 -supported Au nanoparticles were prepared to investigate the intrinsic effect of CeO 2 crystal faces on the oxidation of HMF to 2,5-furandicarboxylic acid (FDCA). The experimental results and density functional theory calculation revealed that the concentration of oxygen vacancy (V O ) for exposed specific crystal faces was crucial to the oxygen adsorption ability, and Au/nanorod-CeO 2 with the highest V O concentration promoted the formation of more oxygen active species (superoxide radical) on CeO 2 (110) crystal face than (100) and (111) crystal faces. Besides, the higher V O concentration could provide a strong adsorption ability of HMF, greatly boosting the activation of HMF. Thus, these results led to a superior catalytic activity for HMF oxidation over Au/nanorod-CeO 2 (FDCA yield of 96.5 %). In-situ Fourier-transform (FT)IR spectroscopy uncovered the HMF oxidation pathway, and the possible catalytic mechanism was proposed. The deep insight into the role of regulation for crystal faces provides a basis for the rational design of highly active facets for the oxidation of HMF and related reactions., (© 2021 Wiley-VCH GmbH.)

2D metal-organic framework (MOF) film as the active layer show promising application prospects in various fields including sensors, catalysis, and electronic devices. However, exploring the application of 2D MOF film in the field of artificial synapses has not been implemented yet. In this work, we fabricated a novel 2D MOF film (Cu-THPP, THPP=5,10,15,20-Tetrakis(4-hydroxyphenyl)-21H,23H-porphine), and further used it as an active layer to explore the application in the simulation of human brain synapses. It shows excellent light-stimulated synaptic plasticity properties, and exhibits the foundation function of synapses such as long-term plasticity (LTP), short-term plasticity (STP), and the conversion of STP to LTP. Most critically, the MOF based artificial synaptic device exhibits an excellent stability in atmosphere. This work opens the door for the application of 2D MOF film in the simulation of human brain synapses., (© 2021 Wiley-VCH GmbH.)

Side-chain engineering is an effective strategy to regulate the solubility and packing behavior of organic materials. Recently, a unique strategy, so-called terminal side-chain (T-SC) engineering, has attracted much attention in the field of organic solar cells (OSCs), but there is a lack of deep understanding of the mechanism. Herein, a new noncovalently fused-ring electron acceptor (NFREA) containing two T-SCs (NoCA-5) was designed and synthesized. Introduction of T-SCs can enhance molecular rigidity and intermolecular π-π stacking, which is confirmed by the smaller Stokes shift value, lower reorganization free energy, and shorter π-π stacking distance in comparison to NoCA-1. Hence, the NoCA-5-based device exhibits a record power conversion efficiency (PCE) of 14.82 % in labs and a certified PCE of 14.5 %, resulting from a high electron mobility, a short charge-extraction time, a small Urbach energy (E u ), and a favorable phase separation., (© 2021 Wiley-VCH GmbH.)

Noncovalently fused-ring electron acceptors (NFREAs) have attracted much attention in recent years owing to their advantages of simple synthetic routes, high yields and low costs. However, the efficiencies of NFREAs based organic solar cells (OSCs) are still far behind those of fused-ring electron acceptors (FREAs). Herein, a series of NFREAs with S⋅⋅⋅O noncovalent intramolecular interactions were designed and synthesized with a two-step synthetic route. Upon introducing π-extended end-groups into the backbones, the electronic properties, charge transport, film morphology, and energy loss were precisely tuned by fine-tuning the degree of multi-fluorination. As a result, a record PCE of 14.53 % in labs and a certified PCE of 13.8 % for NFREAs based devices were obtained. This contribution demonstrated that combining the strategies of noncovalent conformational locks and π-extended end-group engineering is a simple and effective way to explore high-performance NFREAs., (© 2021 Wiley-VCH GmbH.)

The preparation of large-area 2D conductive metal-organic framework (MOF) films remains highly desirable but challenging. Here, inspired by the capillary phenomenon, a face-to-face confinement growth method to grow conductive 2D Cu 2 (TCPP) (TCPP = meso-tetra(4-carboxyphenyl)porphine) MOF films on dielectric substrates is developed. Trace amounts of solutions containing low-concentration Cu 2+ and TCPP are pumped cyclically into a micropore interface to produce this growth. The crystal structures are confirmed with various characterization techniques, which include high-resolution atomic force microscopy and cryogenic transmission electron microscopy (Cryo-TEM). The Cu 2 (TCPP) MOF film exhibit an electrical conductivity of ≈0.007 S cm -1 , which is approximately four orders of magnitude higher than other carboxylic-acid-based MOF materials (10 -6 S cm -1 ). Other wafer-scale conductive MOF films such as M 3 (HHTP) 2 (M = Cu, Co, and Ni; HHTP = 2,3,6,7,10,11-triphenylenehexol) can be produced utilizing this strategy and suggests this method has widescale applicability potential., (© 2021 Wiley-VCH GmbH.)

Owing to their excellent physical and electrical properties, metal-organic framework (MOF) materials with well-defined supramolecular structures have received extensive research attention. However, the fabrication of large-area two-dimensional (2D) MOF films is still a significant challenge. Herein, we propose a novel electrochemical (EC) synthesis method for the preparation of large-area Cu 3 (HHTP) 2 MOF film on single-crystal Cu (100) anode. The surface reaction was achieved via charge-induced molecular assembly. The synthesized MOF film exhibited a high crystalline quality with an electrical conductivity of approximately 0.087 S cm -1 , which was around 1000 times larger than the previously reported values for the same material prepared by the interface method. In addition, Cu 2 (MTCP), Cu 3 (BTPA) 2 , and Cu 3 (TPTC) 2 MOF films were synthesized on Cu foil with the same strategy, which confirmed the universality of the proposed method. This controllable EC method can be effectively applied to the industrial-scale production of 2D MOF films on Cu foil., (© 2020 Wiley-VCH GmbH.)