Fused‐ring electron acceptors have made significant progress in recent years, while the development of fully non‐fused ring acceptors has been unsatisfactory. Here, two fully non‐fused ring ...acceptors, o‐4TBC‐2F and m‐4TBC‐2F, were designed and synthesized. By regulating the location of the hexyloxy chains, o‐4TBC‐2F formed planar backbones, while m‐4TBC‐2F displayed a twisted backbone. Additionally, the o‐4TBC‐2F film showed a markedly red‐shifted absorption after thermal annealing, which indicated the formation of J‐aggregates. For fabrication of organic solar cells (OSCs), PBDB‐T was used as a donor and blended with the two acceptors. The o‐4TBC‐2F‐based blend films displayed higher charge mobilities, lower energy loss and a higher power conversion efficiency (PCE). The optimized devices based on o‐4TBC‐2F gave a PCE of 10.26 %, which was much higher than those based on m‐4TBC‐2F at 2.63 %, and it is one of the highest reported PCE values for fully non‐fused ring electron acceptors.
Two fully non‐fused acceptors are precisely designed and easily prepared. The side chain encapsulation can induce a planar molecular backbone conformation, endowing the acceptor with broad light absorption. Thermal annealing promotes molecular rearrangement to form J‐aggregates with even broader absorption and higher absorption coefficient. A PCE over 10 % is one of the highest PCE for fully non‐fused ring acceptors.
Chemodynamic therapy (CDT) is a new emerging strategy for the in situ treatment of tumors. In the microenvironment of tumor cells, CDT may be achieved through the generation of reactive oxygen ...species (ROS), e.g., hydroxyl radicals (˙OH) and singlet oxygen (
O
), which induce the death of tumor cells. Copper (Cu) or other transition-metal ions catalyze the production of ˙OH by hydrogen peroxide (H
O
) through Fenton or Fenton-like reactions. With the development of advanced nanotechnology, nanotherapeutic systems with Cu-based nanostructures have received extensive attention and have been demonstrated for their wide applications in the design and construction of nanotherapeutic systems for CDT, along with multimodal synergistic therapy. Herein, the cutting-edge developments of Cu-based nanostructures in CDT are reviewed and discussed, by focusing on the monotherapy of CDT as well as synergistic treatments by hyphenating CDT with various therapeutic protocols, e.g., photothermal therapy (PTT), photodynamic therapy (PDT), sonodynamic therapy (SDT), and so on. In addition, the potential challenges and future perspectives are described in the improvement of CDT therapeutic efficacy, the enhancement of targeting capability, and mechanistic investigations on CDT therapy.
Exploring new type of synapse–like electronic devices with fusion of computing and memory is a promising strategy to fundamentally approach to intelligent machines. Herein, organic thin film ...memristors (OTFMs) are achieved, functioning as electrically programmable and erasable analog memory with continuous and nonvolatile device states. The memristive characteristics of OTFMs stem from the asymmetric electrode configuration and the cumulative charge trapping/detrapping in a polymer electret layer, which enables the state–dependent current modulation analogous to the synaptic weight change in biological synapses. OTFMs are demonstrated to successfully emulate the essential synaptic functions, including the reversible potentiation and depression, and the short‐term plasticity such as the paired‐pulse facilitation and the long‐term plasticity such as the spike–timing dependent plasticity.
Organic thin film memristors are achieved based on asymmetric electrode configuration and cumulative charge trapping/detrapping in a polymer electret layer, which function as electrically editable and preservable analog memory. Organic thin film memristors are demonstrated to be capable of emulating both short‐term and long‐term synaptic plasticity, such as the paired‐pulse facilitation and spike‐timing‐dependent plasticity.
The precise identification of single‐atom catalysts (SACs) activity and boosting their efficiency toward CO2 conversion is imperative yet quite challenging. Herein, for the first time a series of ...porous organic polymers is designed and prepared simultaneously, containing well‐defined M–N4 and M–N2O2 single‐atom sites. Such a strategy not only offers multiactive sites to promote the catalytic efficiency but also provides a more direct chance to identify the metal center activity. The CO2 photoreduction results indicate that the introduction of salphen unit with Ni–N2O2 catalytic centers into pristine phthalocyanine‐based Ni–N4 framework achieves remarkable CO generation ability (7.77 mmol g–1) with a high selectivity of 96% over H2. In combination with control experiments, as well as theoretical studies, the Ni–N2O2 moiety is evidenced as a more active site for CO2RR compared with the traditional Ni–N4 moiety, which can be ascribed to the M–N2O2 active sites effectively reducing the energy barrier, facilitating the adsorption of reaction radicals *COOH, and improving the charge transportation. This work might shed some light on designing more efficient SACs toward CO2 reduction through modification of their coordination environments.
Single metal sites with –N4 and –N2O2 coordination mode simultaneously incorporated into one porous organic backbone are reported. With the assistance of experimental results and theoretical calculations, the –N2O2 coordinated single metal sites are identified with higher catalytic activity toward CO2 photoreduction compared to that of traditional –N4 coordinated one.
Rechargeable Li‐O2 batteries have aroused much attention for their high energy density as a promising battery technology; however, the performance of the batteries is still unsatisfactory. Lithium ...anodes, as one of the most important part of Li‐O2 batteries, play a vital role in improving the cycle life of the batteries. Now, a very simple method is introduced to produce a protective film on lithium surface via chemical reactions between lithium metals and 1,4‐dioxacyclohexane. The film is mainly composed of ethylene oxide monomers and endows Li‐O2 batteries with enhanced cycling stability. The film could effectually reduce the morphology changes and suppress the parasitic reactions of lithium anodes. This simple approach provides a new strategy to protect lithium anodes in Li‐O2 batteries.
Protective coating: The stability of lithium anodes plays a vital role in improving the cycle life of Li‐O2 batteries. A convenient method is presented to produce a film on a lithium surface by chemical reactions between lithium metal and 1,4‐dioxacyclohexane. The protective film could reduce the morphology changes and suppress the parasitic reactions of lithium anodes and endow Li‐O2 batteries with enhanced cycling stability.
SUMMARY
Acer truncatum (purpleblow maple) is a woody tree species that produces seeds with high levels of valuable fatty acids (especially nervonic acid). However, the lack of a complete genome ...sequence has limited both basic and applied research on A. truncatum. We describe a high‐quality draft genome assembly comprising 633.28 Mb (contig N50 = 773.17 kb; scaffold N50 = 46.36 Mb) with at least 28 438 predicted genes. The genome underwent an ancient triplication, similar to the core eudicots, but there have been no recent whole‐genome duplication events. Acer yangbiense and A. truncatum are estimated to have diverged about 9.4 million years ago. A combined genomic, transcriptomic, metabonomic, and cell ultrastructural analysis provided new insights into the biosynthesis of very long‐chain monounsaturated fatty acids. In addition, three KCS genes were found that may contribute to regulating nervonic acid biosynthesis. The KCS paralogous gene family expanded to 28 members, with 10 genes clustered together and distributed in the 0.27‐Mb region of pseudochromosome 4. Our chromosome‐scale genomic characterization may facilitate the discovery of agronomically important genes and stimulate functional genetic research on A. truncatum. Furthermore, the data presented also offer important foundations from which to study the molecular mechanisms influencing the production of nervonic acids.
Significance Statement
Here, we provide the first report on the Acer truncatum genome. Our work provides extensive genetic resources necessary for very long‐chain monounsaturated fatty acid biosynthesis.
In recent years, China has experienced severe and persistent air pollution associated with rapid urbanization and climate change. Three years' time series (January 2014 to December 2016) ...concentrations data of air pollutants including particulate matter (PM2.5 and PM10) and gaseous pollutants (SO2, NO2, CO, and O3) from over 1300 national air quality monitoring sites were studied to understand the severity of China's air pollution. In 2014 (2015, 2016), annual population-weighted-average (PWA) values in China were 65.8 (55.0, 50.7) μg m−3 for PM2.5, 107.8 (91.1, 85.7) μg m−3 for PM10, 54.8 (56.2, 57.2) μg m−3 for O3_8 h, 39.6 (33.3, 33.4) μg m−3 for NO2, 34.1 (26, 21.9) μg m−3 for SO2, 1.2 (1.1, 1.1) mg m−3 for CO, and 0.60 (0.59, 0.58) for PM2.5/PM10, respectively. In 2014 (2015, 2016), 7% (14%, 19%), 17% (27%, 34%), 51% (67%, 70%) and 88% (97%, 98%) of the population in China lived in areas that meet the level of annual PM2.5, PM10, NO2, and SO2 standard metrics from Chinese Ambient Air Quality Standards-Grade II. The annual PWA concentrations of PM2.5, PM10, O3_8 h, NO2, SO2, CO in the Northern China are about 40.4%, 58.9%, 5.9%, 24.6%, 96.7%, and 38.1% higher than those in Southern China, respectively. Though the air quality has been improving recent years, PM2.5 pollution in wintertime is worsening, especially in the Northern China. The complex air pollution caused by PM and O3 (the third frequent major pollutant) is an emerging problem that threatens the public health, especially in Chinese mega-city clusters. NOx controls were more beneficial than SO2 controls for improvement of annual PM air quality in the northern China, central, and southwest regions. Future epidemiologic studies are urgently required to estimate the health impacts associated with multi-pollutants exposure, and revise more scientific air quality index standards.
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•Air pollution in China were characterized with three-year observed data.•Population-weighted-average concentrations in provinces, mega-city clusters and regions were calculated.•The complex air pollution caused by PM and O3 is an emerging problem in Chinese mega-city clusters.•Spatial distributions of annual average air pollutants in China were conducted.
Core–shell or striped heteroatomic lanthanide metal–organic framework hierarchical single crystals were obtained by liquid‐phase anisotropic epitaxial growth, maintaining identical periodic ...organization while simultaneously exhibiting spatially segregated structure. Different types of domain and orientation‐controlled multicolor photophysical models are presented, which show either visually distinguishable or visible/near infrared (NIR) emissive colors. This provides a new bottom‐up strategy toward the design of hierarchical molecular systems, offering high‐throughput and multiplexed luminescence color tunability and readability. The unique capability of combining spectroscopic coding with 3D (three‐dimensional) microscale spatial coding is established, providing potential applications in anti‐counterfeiting, color barcoding, and other types of integrated and miniaturized optoelectronic materials and devices.
A colorful turn: Core–shell (see picture, left) or striped (right) heteroatomic lanthanide metal–organic framework hierarchical single crystals are assembled from solution‐mediated epitaxial growth. By manipulation of the domain and orientation, tunable multicolor to white light emissions can be achieved. Multiplexed and high‐throughput capabilities are provided through the combination of spectroscopy with 3D‐space operation.
Three regioregular benzodithiophene‐based donor–donor (D–D)‐type polymers (PBDTT, PBDTT1Cl, and PBDTT2Cl) are designed, synthesized, and used as donor materials in organic solar cells (OSCs). Because ...of the weak intramolecular charge‐transfer effect, these polymers exhibit large optical bandgaps (>2.0 eV). Among these three polymers, PBDTT1Cl exhibits more ordered and closer molecular stacking, and its devices demonstrate higher and more balanced charge mobilities and a longer charge‐separated state lifetime. As a result of these comprehensive benefits, PBDTT1Cl‐based OSCs give a very impressive power conversion efficiency (PCE) of 17.10% with a low nonradiative energy loss (0.19 eV). Moreover, PBDTT1Cl also possesses a low figure‐of‐merit value and good universality to match with different acceptors. This work provides a simply and efficient strategy to design low‐cost high‐performance polymer donor materials.
Three D–D type wide‐bandgap donor polymers (PBDTT, PBDTT1Cl, and PBDTT2Cl) are designed and facilely synthesized. Organic solar cells (OSCs) based on PBDTT1Cl exhibit a high power conversion efficiency of 17% and a low nonradiative energy loss of 0.19 eV. In addition, PBDTT1Cl has a very low figure‐of‐merit and good universality, indicating its potential as a low‐cost polymer donor for high‐performance OSCs.
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