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Perovskite, as a star fluorescent material, has the characteristics of adjustable luminescence peak, high color purity, high photoluminescence quantum yield, and low cost, showing significant potential in the photoelectric field. Among the RGB colors for display devices, green is the most sensitive color for human eyes, and green perovskite light‐emitting diodes (GPeLEDs) have aroused much interest in recent years. In this work, the research history of GPeLEDs is reviewed, the perovskites of different dimensions are introduced, and the common synthesis methods of perovskites are discussed. Besides, the strategies to improve the stability and luminous efficiency of GPeLEDs are summarized, including component engineering, phase engineering, ligand engineering, additive engineering, interface engineering, and optical coupling structure strategy. Finally, the development state of GPeLEDs is summarized and prospected. This work is expected to stimulate more unprecedented achievements derived from GPeLEDs, thus promoting their practical applications in future ultra‐high‐definition displays. [ABSTRACT FROM AUTHOR]

Exploiting narrow-bandwidth-emission fluorescent materials is crucial for next-generation wide-color gamut displays. Inspired by the narrow-bandwidth-emission characteristic of chlorophyll derivates, the present work develops a facile strategy to synthesize a series of red-emitting chlorophyll-structured CDs (CHL-CDs) with ultra-high color purity and good carrier mobility from different traditional Chinese medicine leaves through a simple cross-linking polymerization and carbonization process. The obtained CHL-CDs exhibit bright photoluminescence centered at 671 nm, ultra-high color purity with an FWHM of 23 nm, and a high photoluminescence quantum yield of up to 62%. More importantly, based on in-depth experimental and theoretical studies on the macroscopic host–guest interactions and microscopic interfacial interactions between the CHL-CDs and charge transporting materials, high-performance red electroluminescent light-emitting diodes are successfully prepared, with FWHM of only 28 nm, turn-on voltage of 3.7 V, maximum luminance of 623 cd m−2, and maximum current efficiency of 0.26 cd A−1. This study provides a universal platform for fabricating narrow-bandwidth-emission CDs with significant applications in photoelectric devices. [ABSTRACT FROM AUTHOR]

Wide‐bandgap (WBG) perovskite solar cells (PSCs) have drawn great attention owing to their promising potential for constructing efficient tandem solar cells. However, the rapid crystallization results in poor film properties and easy formation of defects, thereby greatly restricting the acquisition of a small open‐circuit voltage (VOC) deficit due to the severe nonradiative recombination. Herein, it introduced the triethanolamine borate (TB) to effectively slow down the rapid crystallization for preparing highly crystalline and uniform WBG perovskite films with reduced defects. The strong intermolecular interaction (e.g., coordination and hydrogen bond) between TB and perovskite can suppress the halide vacancy formation and inhibit phase segregation for improving long‐term stability. The devices based on a 1.65 eV perovskite absorber achieved a high efficiency of 21.55% with a VOC of 1.24 V, demonstrating the VOC deficit is as low as 0.41 V, which is one of the lowest reports. By combining a semitransparent WBG subcell with a narrow‐bandgap tin‐based PSC, the four‐terminal tandem solar cell delivers a high efficiency of 26.48%. [ABSTRACT FROM AUTHOR]

Alpha‐ketoglutarate‐dependent dioxygenase ALKB homologue 4 (ALKBH4) is a member of the Fe (II) and 2‐oxoglutarate‐dependent ALKB homologue family that plays important roles in epigenetic regulation by alkyl lesions removal in mammals. However, the roles of ALKBH4 in insects are not clear. Here, TcALKBH4 was cloned and functionally characterised in Tribolium castaneum. Temporal expression revealed that TcALKBH4 was highly expressed in early embryos and early pupae. Spatial expression showed that TcALKBH4 was highly expressed in the adult testis, and followed by the ovary. RNA interference targeting TcALKBH4 at different developmental stages in T. castaneum led to apparent phenotypes including the failure of development in larvae, the reduction of food intake and the deficiency of fertility in adult. However, further dot blot analyses showed that TcALKBH4 RNAi does not seem to influence 6 mA levels in vivo. qRT‐PCR was used to further explore the underlying molecular mechanisms; the result showed that TcALKBH4 mediates the development of larvae possibly through 20E signalling pathway, and the fertility of female and male adult might be regulated by the expression of vitellogenesis and JH signalling pathway, respectively. Altogether, these findings will provide new insights into the potential function of ALKBH4 in insects. [ABSTRACT FROM AUTHOR]

Fine‐tuning the thermodynamic self‐assembly of molecules via volatile solid additives has emerged to be an effective way to construct high‐performance organic solar cells. Here, three‐dimensional structured solid molecules have been designed and applied to facilitate the formation of organized molecular assembly in the active layer. By means of systematic theory analyses and film‐morphology characterizations based on four solid candidates, we preselected the optimal one, 4‐fluoro‐N,N‐diphenylaniline (FPA), which possesses good volatility and strong charge polarization. The three‐dimensional solids can induce molecular packing in active layers via strong intermolecular interactions and subsequently provide sufficient space for the self‐reassembly of active layers during the thermodynamic transition process. Benefitting from the optimized morphology with improved charge transport and reduced energy disorder in the FPA‐processed devices, high efficiencies of over 19 % were achieved. The strategy of three‐dimensional additives inducing ordered self‐assembly structure represents a practical approach for rational morphology control in highly efficient devices, contributing to deeper insights into the structural design of efficient volatile solid additives. [ABSTRACT FROM AUTHOR]

Two kinds of triphenylamine‐derived solid‐state emissive carbon dots (CDs) with orange and yellow color are facilely synthesized through solvothermal treatment, taking advantage of the nonplanar structure and good carrier mobility of triphenylamine unit. Theoretical calculations show that the triphenylamine structure could greatly inhibit the direct π–π stacking of aromatic skeletons and enhance the fluorescence properties of CDs in aggregation state. By adopting the CDs as single emissive layer, high‐performance orange‐color and green‐color electroluminescent light‐emitting diodes (LEDs) are successfully fabricated, with maximum brightness of 9450/4236 cd m−2, high current efficiency of 1.57/2.34 cd A−1 and low turn‐on voltage of 3.1/3.6 eV are respectively achieved. Significantly, white‐color LED device is further prepared. This work provides a universal platform for the construction of novel solid‐state emissive CDs with significant applications in photoelectric device. [ABSTRACT FROM AUTHOR]

Crystal growth regulation has become an effective solution to reduce the defects at grain boundaries (GBs) and surfaces of perovskite films for better photovoltaic performances. Oxime acid materials are maturely used as selective collectors in the flotation separation of oxide minerals. Such materials, showing a strong coordination effect and high selectivity with lead, may have great potential in controlling the crystal growth and passivating the defect of perovskite film, which are rarely applied in perovskite solar cells (PerSCs). Herein, an oxime acid‐based material with multi‐coordination sites, ethyl 2‐(2‐aminothiazole‐4‐yl)‐2‐hydroxyiminoacetate (EHA), is incorporated into the PbI2 precursor solution to fabricate high‐performance PerSCs using a two‐step method. The multidentate coordination effect of EHA can link and integrate the PbI2 colloidal clusters to achieve pre‐aggregation in the PbI2 precursor solution, facilitating the sequent crystal growth progress of perovskite film. Meanwhile, EHA can connect grains and fill GBs, which is favorable for charge transfer and passivating both Pb‐I anti‐site and iodine vacancy defects. As a result, the optimal devices show an enhanced efficiency of 24.1% and excellent humidity and thermal stability. This work affords a promising strategy to fabricate efficient and stable PerSCs via multidentate coordination‐induced crystallization control and GB passivation. [ABSTRACT FROM AUTHOR]

High-efficiency optoelectronic devices are attracting extensive attention nowadays. Besides efficiency, cost and long-term stability are also crucial parameters for judging the performance and application of optoelectronic devices. Multilayer solution processing technology has been proved to be an ideal and low-cost strategy. However, one of the key factors restricting this strategy is solvent erosion during subsequent solution-based device processing. Besides, the long-term stability is of vital significance for the lifetime of optoelectronic devices. Therefore, exploiting solvent-resistant and durable materials is urgently needed. Promisingly, crosslinkable organic semiconductors (COSs) can be crosslinked into an insoluble and stable network structure to achieve solvent resistance and improve long-term stability. In this review, the recent advances in COSs used in optoelectronic devices (organic photovoltaics (OPVs), perovskite solar cells (PerSCs), and organic light-emitting diodes (OLEDs)) are systematically summarized, in which the basic considerations and key challenges to realize solvent resistance and enhance long-term stability are presented first. Then, the significance, strategies, and disadvantages of COSs are introduced. Finally, typical applications of COSs in OPVs, OLEDs, and PerSCs and their prospects are discussed and highlighted. This review is expected to attract further considerable interest in COSs and promote further progress in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Interface engineering plays a vital role in the further improvement of efficiency and stability for organic solar cells (OSCs). Herein, a self‐assembly metal chelate based on hafnium and a designed ligand, N‐(4‐(3‐oxobutanoyl)phenyl)acetamide (ACBN) is applied as both interfacial modification layer and UV‐light filter in OSCs. The strong hydrogen‐bond induced intermolecular interaction enables Hf(ACBN)4 with the prerequisite of adequate solvent resistance to work as an electron transport layer (ETL) in the inverted OSCs. The self‐assembly behavior of Hf(ACBN)4 on the SnO2 film surface via constructing compact coordination structure has been verified via systematic theory calculations. In addition to optimizing the energy level alignment, the Hf(ACBN)4 modification effectively passivates the surface defect of SnO2 films for less surface charge recombination and a more efficient charge collection process. Thus, the OSCs with Hf(ACBN)4 layer yield a maximum PCE of 18.1%, better than that based on the bare SnO2 layer. Moreover, beneficial from the reduced oxygen vacancies via coordination effect and the UV‐light filter function of Hf(ACBN)4, the OSCs based on SnO2/ Hf(ACBN)4 composite ETL exhibit preferable stabilities under UV‐light irradiation or continuous operational conditions. [ABSTRACT FROM AUTHOR]

Background: Insect cytochrome P450 monooxygenases (P450s) play a crucial role in phytochemical metabolism and tolerance. Three P450 genes (TcCYP4Q3, TcCYP4Q5, and TcCYP4Q7) are associated with the response of eugenol in Tribolium castaneum. However, the responding mechanisms of these P450 genes to eugenol remain unknown. Results: Here, spatiotemporal expression profiling revealed that TcCYP4Q3 and TcCYP4Q5 were most highly expressed in late adult, while TcCYP4Q7 was predominantly expressed in late larva; and all of these three P450 genes were mainly expressed in the fat body of larvae. Furthermore, the expressions of these three P450 genes were significantly up‐regulated after exposure to eugenol, and depletion of them enhanced the susceptibility of beetles to eugenol. Interestingly, RNA interference (RNAi) against the CncC gene, a transcription factor of CncC signaling pathway associated with regulation of insect P450s in response to phytochemicals, reduced the transcripts of these three P450 genes following exposure to eugenol. Investigation of CncC signaling pathway showed that this pathway could be activated by eugenol. Conclusion: Altogether, the results indicate that these three P450 genes are regulated by CncC signaling pathway to participate in the susceptibility of Tribolium castaneum to phytochemicals. These findings will aid implications for the development of novel therapeutics to control pest. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In recent years, increasing numbers of microRNAs (miRNAs) have been reported to regulate insect metamorphosis. One thousand, one hundred fifty‐four miRNAs have been previously identified from Tribolium castaneum by high‐throughput sequencing; however, little is known about which miRNAs can participate in metamorphosis, leaving the role of miRNAs in regulating the underlying mechanism elusive. Here, we report the participation of miR‐3017b in the metamorphosis of T. castaneum. Temporal profiles revealed that miR‐3017b was highly expressed at the late larval stage, but significantly decreased at the early pupal stage. Overexpression of miR‐3017b caused larval to pupal to adult metamorphosis arrested. Dual‐luciferase reporter assay and miRNA–mRNA interaction assay illustrated that miR‐3017b interacts with the coding sequence of sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) and suppresses its expression. Knockdown of SERCA caused metamorphosis arrested, similar to that observed in miR‐3017b overexpression beetles. Further functional mechanism analyses revealed that 20‐hydroxyecdysone application downregulates miR‐3017b and up‐regulates SERCA expression. The expression level of downstream genes in the 20E pathway was disrupted after overexpressing miR‐3017 and the knockdown of SERCA. These results provided evidence miR‐3017b‐SERCA contributes to metamorphosis by regulating the 20E pathway in T. castaneum. It could advance our understanding of the coordination of 20E and miRNA regulation in insect metamorphosis. [ABSTRACT FROM AUTHOR]

Sensible selection of host blends and the third component is crucial to give full play to the advantages of the ternary strategy for achieving high efficiency polymer solar cells (PSCs). In this work, a PM6:BTP-BO-4Cl binary system and non-fullerene acceptor DTTC-4ClC9 with the dithienocyclopentacarbazole (DTC) core are selected as the host blend and the third component, respectively. DTTC-4ClC9 and BTP-BO-4Cl are found to have excellent miscibility, and the addition of DTTC-4ClC9 into the binary blend can modify the morphology of the film, which brings out an improved charge transport and obviously enhanced exciton dissociation ability. The non-radiative energy loss of the devices is significantly reduced to 0.207 eV when employing the ternary strategy, thus leading to a reduction in energy loss. As a result, the introduction of 15% DTTC-4ClC9 in the PM6:BTP-BO-4Cl system can promote the power conversion efficiency from 17.11% to remarkable 18.21%, meanwhile, the open-circuit voltage, short-circuit current density, and fill factor are increased simultaneously. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) is broadly used as an electron transport layer (ETL) in organic solar cells (OSCs). However, there are many hydroxyl groups and the defects of oxygen vacancy on the surface of SnO2, resulting in charge recombination. Herein, an electrolyte 4‐(dimethyl(pyridin‐2‐yl) ammonio)butane‐1‐sulfonate (PAS) is doped into SnO2 films with an appropriate proportion to improve the performance of the inverted OSCs. The PAS can coordinate with the Sn atoms in SnO2 films to reduce the surface defects, resulting adjustable work function and increased electron conductivity. Meanwhile, the PAS doping can decrease the surface energy of SnO2 layer, forming vertical phase distribution of the active layer for better exciton dissociation and charge transport. The PM6:Y6 based inverted OSC with SnO2 ETL shows a power conversion efficiency (PCE) of 14.72%, while the device with PAS‐doped SnO2 ETL demonstrates greatly enhanced PCE of 16.37%. The device performance can be further improved by using PM6:BTP‐eC9 as active layer and a PCE of 17.12% can be achieved with PAS‐doped SnO2 ETL. Furthermore, PAS‐doped SnO2 can effectively enhance the device stability under continuous illumination. These findings demonstrate that exquisite regulation of SnO2 layer via a small electrolyte molecule coordination is a promising approach to achieve efficient and stable inverted OSCs. [ABSTRACT FROM AUTHOR]

Semitransparent organic and perovskite solar cells are considered promising photovoltaic (PV) devices that can be applied to power‐generating windows and facades of modern buildings and have achieved great progress in the past few years. Different from silicon‐based solar cells, the optical absorption of devices with organic and perovskite active layer materials can be easily tuned by modifying the chemical structure and adjusting the halide types or contents, respectively, to meet the demands of energy‐generating windows. In this review, the development progress of semitransparent PV (STPV) in terms of the selection of active layer materials, top transparent electrodes (TTEs), and strategies of enhancing the performance of STPVs is introduced. Meanwhile, the challenges and outlooks for the future development of STPVs are discussed. [ABSTRACT FROM AUTHOR]

Interfacial modification is an effective method to improve the performance of polymer solar cells (PSCs), and molybdenum oxide is one of the most widely used anode buffer layer (ABL) materials in PSCs. However, the complicated preparations with high‐temperature annealing or vacuum deposition make it uneconomic. Herein, a facile method to prepare MoOx solution in 1‐hexanol is proposed, and the component of the product can be simply adjusted by controlling the amount of introduced water. The added water facilitates the generation of α‐MoO3 microcrystals. To the best of our knowledge, this is also the first report to obtain α‐MoO3 through such a simple method. The obtained MoOx solutions are utilized to fabricate ABL in high efficiency PSCs to improve the performance. High temperature treatment is omitted, while the PCEs of binary and ternary devices can be enhanced to 16.09% and 16.81%, respectively, significantly higher than the devices with PEDOT:PSS ABL (15.55% and 15.93%). Herein, an efficient method to prepare MoOx solution in 1‐hexanol with controlled component is offered, and it is demonstrated that the MoOx ABL derived from the MoOx solution is a potential replacement to enhance the performance of high efficiency PSCs. [ABSTRACT FROM AUTHOR]

Carbon dot (CD)-based room temperature phosphorescence (RTP) nanomaterials have constituted a research hotspot in multidisciplinary fields. Among the promising RTP CDs, fluorescence–phosphorescence dual emissive CDs (FP-CDs) are currently drawing enormous attention. Herein, highly efficient blue-green FP-CDs were easily prepared by a solvent-free pyrolysis treatment of hydroxyurea. The obtained FP-CDs showed high photoluminescence and phosphorescence quantum yields of 21% and 13%, respectively. Detailed experimental characterization revealed that the efficient dual-emission property is derived from the aromatic carbonyl groups at the edge of FP-CDs. Benefiting from the unique optical performance, FP-CDs exhibited good potential in anticounterfeiting and information encryption. This study offers a new strategy for developing dual-emission fluorescence–phosphorescence nanomaterials. [ABSTRACT FROM AUTHOR]

Organic tandem solar cells (OTSCs) with the merits of overcoming the S‐Q limit of single‐junction, enhancing and expanding the sunlight harvesting, and minimizing the thermalization energy loss, provide a practical strategy to break through the power conversion efficiency (PCE). However, it is still challenge to realize the multilayered structure by all‐solution processing, especially shortage of interconnection layer (ICL), which physically and electronically connects front and rear subcells to accomplish the complicated tandem structure. Herein, all‐solution‐processed ICL of modified poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (m‐PEDOT) and titanium (diisopropoxide) bis(2,4‐pentanedionate) (TIPD) is invented for constructing inverted OTSCs, and by systematically managing the light and carriers within the stacked multilayers, highly efficient OTSCs are demonstrated. Compared with the traditional ICLs, it avoids the complicated vacuum evaporation and synthesis processes, guaranteeing low cost and high reproducibility. Furthermore, m‐PEDOT/TIPD ICL demonstrates excellent solvent resistance, high transmittance, and good conductivity. To enhance the light harvesting, absorption complementary donors and acceptors are selected as photoactive materials in front and rear subcells, and the transfer matrix formalism optical modeling is introduced to achieve the balanced short‐circuit current density of each subcell in OTSCs. By systematic device optimizations, the best PCE of 15.26% is achieved, among the best results reported for OTSCs. [ABSTRACT FROM AUTHOR]

The photovoltaic performance of organic solar cells (OSCs) based on poly(3‐hexylthiophene) (P3HT) has been steadily improved by developing novel non‐fullerene acceptors (NFAs) in recent years. Herein, to further improve the performance of P3HT‐based OSCs, a solid additive (SA4) and a typical solvent additive [1,8‐diiodooctane (DIO)] were employed to process P3HT:ZY‐4Cl‐based OSCs, respectively. In comparison with the DIO‐processed device, the SA4‐processed one exhibited a more ordered molecular packing and more favorable phase separation, leading to enhanced charge transport and reduced carrier recombination. As a result, the SA4‐processed device delivered a power conversion efficiency (PCE) of 10.24 %, which was much higher than that of the DIO‐processed counterpart (6.26 %). This work reported a PCE over 10 % in P3HT‐based OSCs for the first time, indicating the promising development of P3HT‐based OSCs by morphological modulation. [ABSTRACT FROM AUTHOR]

The development of efficient and stable interface materials is an important part of the research in organic photovoltaics (OPVs), which aims to realize higher efficiency, longer lifetime, lower cost, easier fabrication, and wider applicability. MoO3 exhibits a suitable work function, adjustable electronic structure, favorable ohmic contact with organic materials, remarkable stability in the presence of water and oxygen, and excellent solution processing properties, making it an ideal anode buffer layer (ABL) for OPVs. This review analyzes the photoelectric characteristics of MoO3 based on the crystalline structure and its fundamentals as an ABL in OPVs. To simplify the fabrication procedure, AHM, MoO2(acac)2, and MoO3 powder are used as precursors for solution processing MoO3 buffer layers, and the attempts are still ongoing. Strategies of composite/hybrid formation, modification and doping are utilized to optimize the MoO3 ABL to obtain more efficient and stable OPVs. Combining the optical and electronic properties of MoO3, diverse applications are introduced in inverted, semi-transparent devices and tandem architectures, showing the wide applicability of MoO3 in OPVs. This review draws the outline of the relationships between the composition, structure and processing method of MoO3 and device performance, and further studies to fully understand it at a deeper level are highly needed, which is beneficial to improve the performance of OPVs and the research for solar cells with a similar structure, such as perovskite solar cells. [ABSTRACT FROM AUTHOR]

TCNQ is applied in the non-fullerene-based active layer to fully investigate its effect on the film morphology and photovoltaic performance. Facilitated by the introduction and volatilization of TCNQ after thermal annealing, optimized film morphology with a better phase separation structure is achieved, leading to higher power conversion efficiency. [ABSTRACT FROM AUTHOR]

A ternary organic solar cell, consisting of two compatible non-fullerene acceptors and one wide band-gap donor, with a high efficiency of over 14% is reported, and the working mechanism of the bandgap structure modulation is studied. Based on that, we fabricate six-component OSCs by selecting one donor and five non-fullerene acceptors, exhibiting easily tuned current and voltage. [ABSTRACT FROM AUTHOR]

Abstract: The use of a ternary component is a facile and effective method to further improve the device performances of binary organic solar cells (OSCs) comprising one donor and one acceptor. Recently, the rapid progress of highly efficient nonfullerene acceptor materials has offered a new opportunity for studying ternary OSCs because of the flexibility of ternary components, and the photovoltaic performance of ternary OSCs has been promoted quickly. In this research news article, some strategies for materials selection of the ternary components are concisely summarized and the recent progress in ternary OCSs based on nonfullerene acceptors, and the challenges and perspectives of ternary OSCs are also presented. [ABSTRACT FROM AUTHOR]