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901.
A novel free-standing pie-like paper electrode composed of Mo2C nanobeads on graphene-coated carbon nanofibers (G-CNF) membrane was rationally designed as advanced electrocatalyst for hydrogen evolution reaction (HER). A thin layer of graphene is coated on the surface of CNF membrane, forming a “crust” on fibrous web architecture. The unique design of the all-carbon membrane, which is a 3D interconnected conductive framework of nanofibers, reduces the resistance of electron and ion transport during the electrocatalyzing process. With G-CNF performing as support, well-shaped Mo2C nanobeads were immobilized on the fibers through hydrothermal and calcination procedures, offering rich catalytic sites on the exposed rough surface. Owing to all these merits, the composite membrane of Mo2C-G-CNF exhibits high HER catalytic activity with onset potential of 115 mV in acidic solution and 108 mV in basic solution. Furthermore, the good durability in both acidic and basic environment guarantees its practical application as free-standing electrode material. 相似文献
902.
Hao Zhang Prof. Wanchun Xiang Xuejiao Zuo Xiaojing Gu Shiang Zhang Yachao Du Zhiteng Wang Yali Liu Haifeng Wu Peijun Wang Qingyue Cui Hang Su Prof. Qingwen Tian Prof. Shengzhong Liu 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216634
Minimizing surface defect is vital to further improve power conversion efficiency (PCE) and stability of inorganic perovskite solar cells (PSCs). Herein, we designed a passivator trifluoroacetamidine (TFA) to suppress CsPbI3−xBrx film defects. The amidine group of TFA can strongly chelate onto the perovskite surface to suppress the iodide vacancy, strengthened by additional hydrogen bonds. Moreover, three fluorine atoms allow strong intermolecular connection via intermolecular hydrogen bonds, thus constructing a robust shield against moisture. The TFA-treated PSCs exhibit remarkably suppressed recombination, yielding the record PCEs of 21.35 % and 17.21 % for 0.09 cm2 and 1.0 cm2 device areas, both of which are the highest for all-inorganic PSCs so far. The device also achieves a PCE of 39.78 % under indoor illumination, the highest for all-inorganic indoor photovoltaic devices. Furthermore, TFA greatly improves device ambient stability by preserving 93 % of the initial PCE after 960 h. 相似文献
903.
Xiang-Ji Liao Dongdong Pu Li Yuan Jingjing Tong Shuai Xing Dr. Zhen-Long Tu Prof. Jing-Lin Zuo Prof. Wen-Hua Zheng Prof. You-Xuan Zheng 《Angewandte Chemie (International ed. in English)》2023,62(6):e202217045
Chiral boron/nitrogen doped multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising for highly efficient and color-pure circularly polarized organic light-emitting diodes (CP-OLEDs). Herein, we report two pairs of MR-TADF materials (Czp-tBuCzB, Czp-POAB) based on planar chiral paracyclophane with photoluminescence quantum yields of up to 98 %. The enantiomers showed symmetric circularly polarized photoluminescence spectra with dissymmetry factors |gPL| of up to 1.6×10−3 in doped films. Meanwhile, the sky-blue CP-OLEDs with (R/S)-Czp-tBuCzB showed an external quantum efficiency of 32.1 % with the narrowest full-width at half-maximum of 24 nm among the reported CP-OLEDs, while the devices with (R/S)-Czp-POAB displayed the first nearly pure green CP electroluminescence with |gEL| factors at the 10−3 level. These results demonstrate the incorporation of planar chirality into MR-TADF emitter is a reliable strategy for constructing of efficient CP-OLEDs. 相似文献
904.
Prof. Dr. Wenhuan Huang Chenyang Su Dr. Chen Zhu Dr. Tingting Bo Dr. Shouwei Zuo Prof. Wei Zhou Yuanfu Ren Prof. Yanan Zhang Prof. Jing Zhang Prof. Magnus Rueping Prof. Huabin Zhang 《Angewandte Chemie (International ed. in English)》2023,62(25):e202304634
The solar-driven evolution of hydrogen from water using particulate photocatalysts is considered one of the most economical and promising protocols for achieving a stable supply of renewable energy. However, the efficiency of photocatalytic water splitting is far from satisfactory due to the sluggish electron-hole pair separation kinetics. Herein, isolated Mo atoms in a high oxidation state have been incorporated into the lattice of Cd0.5Zn0.5S (CZS@Mo) nanorods, which exhibit photocatalytic hydrogen evolution rate of 11.32 mmol g−1 h−1 (226.4 μmol h−1; catalyst dosage 20 mg). Experimental and theoretical simulation results imply that the highly oxidized Mo species lead to mobile-charge imbalances in CZS and induce the directional photogenerated electrons transfer, resulting in effectively inhibited electron-hole recombination and greatly enhanced photocatalytic efficiency. 相似文献
905.
Dr. Guixiang Li Dr. Yalei Hu Prof. Dr. Meng Li Ying Tang Zuhong Zhang Dr. Artem Musiienko Qing Cao Fatima Akhundova Jinzhao Li Karunanantharajah Prashanthan Dr. Fengjiu Yang Patryk Janasik Augustine N. S. Appiah Sergei Trofimov Nikolaos Livakas Shengnan Zuo Luyan Wu Luyao Wang Dr. Yuqian Yang Dr. Benjamin Agyei-Tuffour Dr. Rowan W. MacQueen Dr. Boris Naydenov Dr. Thomas Unold Prof. Dr. Eva Unger Dr. Ece Aktas Prof. Dr. Siegfried Eigler Prof. Dr. Antonio Abate 《Angewandte Chemie (International ed. in English)》2023,62(39):e202307395
Stability issues could prevent lead halide perovskite solar cells (PSCs) from commercialization despite it having a comparable power conversion efficiency (PCE) to silicon solar cells. Overcoming drawbacks affecting their long-term stability is gaining incremental importance. Excess lead iodide (PbI2) causes perovskite degradation, although it aids in crystal growth and defect passivation. Herein, we synthesized functionalized oxo-graphene nanosheets (Dec-oxoG NSs) to effectively manage the excess PbI2. Dec-oxoG NSs provide anchoring sites to bind the excess PbI2 and passivate perovskite grain boundaries, thereby reducing charge recombination loss and significantly boosting the extraction of free electrons. The inclusion of Dec-oxoG NSs leads to a PCE of 23.7 % in inverted (p-i-n) PSCs. The devices retain 93.8 % of their initial efficiency after 1,000 hours of tracking at maximum power points under continuous one-sun illumination and exhibit high stability under thermal and ambient conditions. 相似文献
906.
Tong Hong Song Cheng Xuefang Zhong Yiwei Zuo Yiming Dong Zhichuan Shi Zhigang Zhao 《中国化学会会志》2023,70(2):136-144
A novel dicoumarin-derived hydrogen sulfide (H2S) selective fluorescent “turn-on” probe 3-(2,4-dinitrobenzenesulfonate)-dicoumarin (DC-HS) created by covalent bonding between the 2,4-dinitrobenzenesulfonyl (DNBS) and the 3-hydroxy-dicoumarin (DC-OH) units. Upon the addition of H2S, the probe DC-HS solution's fluorescence significantly increased, and its appearance is changed from practically colorless to brilliant yellow. Probe DC-HS also showed significant fluorescence amplification that was quantitatively detectable in the concentration range of 0–1.5 μM and had a low detection limit or limit of detection of 0.2 nM. Moreover, with a high recovery rate and excellent accuracy, the developed fluorescent molecule was used successfully for the analysis of H2S in red wine samples. 相似文献
907.
Haoran Zheng Dr. Haidong Li Dr. Mingqiang Li Dr. Tingting Zhai Dr. Xiaodong Xie Cong Li Dr. Xinxin Jing Dr. Chengpin Liang Prof. Qian Li Prof. Xiaolei Zuo Prof. Jiang Li Prof. Jiangli Fan Dr. Jianlei Shen Prof. Xiaojun Peng Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2023,62(35):e202305896
Membrane curvature reflects physical forces operating on the lipid membrane, which plays important roles in cellular processes. Here, we design a mechanosensitive DNA (MSD) nanomachine that mimics natural mechanosensitive PIEZO channels to convert the membrane tension changes of lipid vesicles with different sizes into fluorescence signals in real time. The MSD nanomachine consists of an archetypical six-helix-bundle DNA nanopore, cholesterol-based membrane anchors, and a solvatochromic fluorophore, spiropyran (SP). We find that the DNA nanopore effectively amplifies subtle variations of the membrane tension, which effectively induces the isomerization of weakly emissive SP into highly emissive merocyanine isomers for visualizing membrane tension changes. By measuring the membrane tension via the fluorescence of MSD nanomachine, we establish the correlation between the membrane tension and the curvature that follows the Young-Laplace equation. This DNA nanotechnology-enabled strategy opens new routes to studying membrane mechanics in physiological and pathological settings. 相似文献
908.
Pei Zhou Hui Liu Xin Meng Huiyun Zuo Mengya Qi Dr. Liang Guo Dr. Cong Gao Dr. Wei Song Prof. Jing Wu Prof. Xiulai Chen Prof. Wei Chen Prof. Liming Liu 《Angewandte Chemie (International ed. in English)》2023,62(14):e202215778
Microbial cell factories provide a green and sustainable opportunity to produce value-added products from renewable feedstock. However, the leakage of toxic or volatile intermediates decreases the efficiency of microbial cell factories. In this study, membraneless organelles (MLOs) were reconstructed in Saccharomyces cerevisiae by the disordered protein sequence A-IDPs. A regulation system was designed to spatiotemporally regulate the size and rigidity of MLOs. Manipulating the MLO size of strain ZP03-FM, the amounts of assimilated methanol and malate were increased by 162 % and 61 %, respectively. Furthermore, manipulating the MLO rigidity in strain ZP04-RB made acetyl-coA synthesis from oxidative glycolysis change to non-oxidative glycolysis; consequently, CO2 release decreased by 35 % and the n-butanol yield increased by 20 %. This artificial MLO provides a strategy for the co-localization of enzymes to channel C1 starting materials into value-added chemicals. 相似文献
909.
Dr. Yang Lv Dr. Si-Wen Ke Dr. Yuming Gu Bailin Tian Lingyu Tang Pan Ran Dr. Yue Zhao Prof. Jing Ma Prof. Jing-Lin Zuo Prof. Mengning Ding 《Angewandte Chemie (International ed. in English)》2023,62(27):e202305246
Nitrate-containing industrial wastewater poses a serious threat to the global food security and public health safety. As compared to the traditional microbial denitrification, electrocatalytic nitrate reduction shows better sustainability with ultrahigh energy efficiency and the production of high-value ammonia (NH3). However, nitrate-containing wastewater from most industrial processes, such as mining, metallurgy, and petrochemical engineering, is generally acidic, which contradicts the typical neutral/alkaline working conditions for both denitrifying bacteria and the state-of-the-art inorganic electrocatalysts, leading to the demand for pre-neutralization and the problematic hydrogen evaluation reaction (HER) competition and catalyst dissolution. Here, we report a series of Fe2M (M=Fe, Co, Ni, Zn) trinuclear cluster metal–organic frameworks (MOFs) that enable the highly efficient electrocatalytic nitrate reduction to ammonium under strong acidic conditions with excellent stability. In pH=1 electrolyte, the Fe2Co-MOF demonstrates the NH3 yield rate of 20653.5 μg h−1 mg−1site with 90.55 % NH3-Faradaic efficiency (FE), 98.5 % NH3-selectivity and up to 75 hr of electrocatalytic stability. Additionally, successful nitrate reduction in high-acidic conditions directly produce the ammonium sulfate as nitrogen fertilizer, avoiding the subsequent aqueous ammonia extraction and preventing the ammonia spillage loss. This series of cluster-based MOF structures provide new insights into the design principles of high-performance nitrate reduction catalysts under environmentally-relevant wastewater conditions. 相似文献
910.
Zi-Han Zhao Dr. Pei-Chen Zhao Shi-Yi Chen Prof. You-Xuan Zheng Prof. Jing-Lin Zuo Prof. Cheng-Hui Li 《Angewandte Chemie (International ed. in English)》2023,62(22):e202301993
Room-temperature phosphorescence (RTP) polymers, whose emission can persist for a long period after photoexcitation, are of great importance for practical applications. Herein, dynamic covalent boronic ester linkages with internal B−N coordination are incorporated into a commercial epoxy matrix. The reversible dissociation of B−N bonds upon loading provides an efficient energy dissipation pathway for the epoxy network, while the rigid epoxy matrix can inhibit the quenching of triplet excitons in boronic esters. The obtained polymers exhibit enhanced mechanical toughness (12.26 MJ m−3), ultralong RTP (τ=540.4 ms), and shape memory behavior. Notably, there is no apparent decrease in the RTP property upon prolonged immersion in various solvents because the networks are robust. Moreover, the dynamic bonds endow the polymers with superior reprocessablity and recyclability. These novel properties have led to their potential application for information encryption and anti-counterfeiting. 相似文献