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991.
Guangming Wang Shunhua Chen Qiwei Duan Fenfei Wei Prof. Sen Lin Prof. Zailai Xie 《Angewandte Chemie (International ed. in English)》2023,62(38):e202307470
Borocarbonitride (BCN) materials are newly developed oxidative dehydrogenation catalysts that can efficiently convert alkanes to alkenes. However, BCN materials tend to form bulky B2O3 due to over-oxidation at the high reaction temperature, resulting in significant deactivation. Here, we report a series of super stable BCN nanosheets for the oxidative dehydrogenation of propane (ODHP) reaction. The catalytic performance of the BCN nanosheets can be easily regulated by changing the guanine dosage. The control experiment and structural characterization indicate that the introduction of a suitable amount of carbon could prevent the formation of excessive B2O3 from BCN materials and maintain the 2D skeleton at a high temperature of 520 °C. The best-performing catalyst BCN exhibits 81.9 % selectivity towards olefins with a stable propane conversion of 35.8 %, and the propene productivity reaches 16.2 mmol h−1 g−1, which is much better than hexagonal BN (h-BN) catalysts. Density functional theory calculation results show that the presence of dispersed rather than aggregated carbon atoms can significantly affect the electronic microenvironment of h-BN, thereby boosting the catalytic activity of BCN. 相似文献
992.
Ziwei Xu Hongwei Dong Dr. Wanmiao Gu Dr. Zhen He Fengming Jin Dr. Chengming Wang Dr. Qing You Prof. Dr. Jin Li Prof. Dr. Haiteng Deng Dr. Lingwen Liao Dr. Dong Chen Prof. Dr. Jun Yang Prof. Dr. Zhikun Wu 《Angewandte Chemie (International ed. in English)》2023,62(39):e202308441
Lattice tuning at the ≈1 nm scale is fascinating and challenging; for instance, lattice compression at such a minuscule scale has not been observed. The lattice compression might also bring about some unusual properties, which waits to be verified. Through ligand induction, we herein achieve the lattice compression in a ≈1 nm gold nanocluster for the first time, as detected by the single-crystal X-ray crystallography. In a freshly synthesized Au52(CHT)28 (CHT=S-c−C6H11) nanocluster, the lattice distance of the (110) facet is found to be compressed from 4.51 to 3.58 Å at the near end. However, the lattice distances of the (111) and (100) facets show no change in different positions. The lattice-compressed nanocluster exhibits superior electrocatalytic activity for the CO2 reduction reaction (CO2RR) compared to that exhibited by the same-sized Au52(TBBT)32 (TBBT=4-tert-butyl-benzenethiolate) nanocluster and larger Au nanocrystals without lattice variation, indicating that lattice tuning is an efficient method for tailoring the properties of metal nanoclusters. Further theoretical calculations explain the high CO2RR performance of the lattice-compressed Au52(CHT)28 and provide a correlation between its structure and catalytic activity. 相似文献
993.
Dr. Shi Xuan Leong Dr. Ya-Chuan Kao Dr. Xuemei Han Dr. Zhong Wei Poh Jaslyn Ru Ting Chen Emily Xi Tan Yong Xiang Leong Dr. Yih Hong Lee Dr. Wei Xuan Teo Prof. George W. Yip Prof. Yulin Lam Prof. Xing Yi Ling 《Angewandte Chemie (International ed. in English)》2023,62(44):e202309610
Molecular recognition of complex isomeric biomolecules remains challenging in surface-enhanced Raman scattering (SERS) spectroscopy due to their small Raman cross-sections and/or poor surface affinities. To date, the use of molecular probes has achieved excellent molecular sensitivities but still suffers from poor spectral specificity. Here, we induce “charge and geometry complementarity” between probe and analyte as a key strategy to achieve high spectral specificity for effective SERS molecular recognition of structural analogues. We employ 4-mercaptopyridine (MPY) as the probe, and chondroitin sulfate (CS) disaccharides with isomeric sulfation patterns as our proof-of-concept study. Our experimental and in silico studies reveal that “charge and geometry complementarity” between MPY's binding pocket and the CS sulfation patterns drives the formation of site-specific, multidentate interactions at the respective CS isomerism sites, which “locks” each CS in its analogue-specific complex geometry, akin to molecular docking events. Leveraging the resultant spectral fingerprints, we achieve > 97 % classification accuracy for 4 CSs and 5 potential structural interferences, as well as attain multiplex CS quantification with < 3 % prediction error. These insights could enable practical SERS differentiation of biologically important isomers to meet the burgeoning demand for fast-responding applications across various fields such as biodiagnostics, food and environmental surveillance. 相似文献
994.
Dr. Hongshuang Guo Dr. Chen Liang Dr. Tero-Petri Ruoko Dr. Henning Meteling Dr. Bo Peng Dr. Hao Zeng Prof. Arri Priimagi 《Angewandte Chemie (International ed. in English)》2023,62(43):e202309402
Shape-changing polymeric materials have gained significant attention in the field of bioinspired soft robotics. However, challenges remain in versatilizing the shape-morphing process to suit different tasks and environments, and in designing systems that combine reversible actuation and self-healing ability. Here, we report halogen-bonded liquid crystal elastomers (LCEs) that can be arbitrarily shape-programmed and that self-heal under mild thermal or photothermal stimulation. We incorporate halogen-bond-donating diiodotetrafluorobenzene molecules as dynamic supramolecular crosslinks into the LCEs and show that these relatively weak crosslinks are pertinent for their mechanical programming and self-healing. Utilizing the halogen-bonded LCEs, we demonstrate proof-of-concept soft robotic motions such as crawling and rolling with programmed velocities. Our results showcase halogen bonding as a promising, yet unexplored tool for the preparation of smart supramolecular constructs for the development of advanced soft actuators. 相似文献
995.
Xiaofang Bai Xiuping Zhang Yujiao Sun Mingcheng Huang Prof. Dr. Jiantao Fan Prof. Dr. Shaoyi Xu Prof. Dr. Hui Li 《Angewandte Chemie (International ed. in English)》2023,62(38):e202308704
To date, only a few noble metal oxides exhibit the required efficiency and stability as oxygen evolution reaction (OER) catalysts under the acidic, high-voltage conditions that exist during proton exchange membrane water electrolysis (PEMWE). The high cost and scarcity of these catalysts hinder the large-scale application of PEMWE. Here, we report a novel OER electrocatalyst for OER comprised of uniformly dispersed Ru clusters confined on boron carbon nitride (BCN) support. Compared to RuO2, our BCN-supported catalyst shows enhanced charge transfer. It displays a low overpotential of 164 mV at a current density of 10 mA cm−2, suggesting its excellent OER catalytic activity. This catalyst was able to operate continuously for over 12 h under acidic conditions, whereas RuO2 without any support fails in 1 h. Density functional theory (DFT) calculations confirm that the interaction between the N on BCN support and Ru clusters changes the adsorption capacity and reduces the OER energy barrier, which increases the electrocatalytic activity of Ru. 相似文献
996.
Chieh-Ming Hung Chi-Lun Mai Chi-Chi Wu Bo-Han Chen Chih-Hsuan Lu Che-Chun Chu Meng-Chuan Wang Prof. Shang-Da Yang Prof. Hsieh-Chih Chen Prof. Chen-Yu Yeh Prof. Pi-Tai Chou 《Angewandte Chemie (International ed. in English)》2023,62(40):e202309831
Self-assembled monolayers (SAMs) offer the advantage of facile interfacial modification, leading to significant improvements in device performance. In this study, we report the design and synthesis of a new series of carboxylic acid-functionalized porphyrin derivatives, namely AC-1, AC-3, and AC-5, and present, for the first time, a strategy to exploit the large π-moiety of porphyrins as a backbone for interfacing the indium tin oxide (ITO) electrode and perovskite active layer in an inverted perovskite solar cell (PSC) configuration. The electron-rich nature of porphyrins facilitates hole transfer and the formation of SAMs, resulting in a dense surface that minimizes defects. Comprehensive spectroscopic and dynamic studies demonstrate that the double-anchored AC-3 and AC-5 enhance SAMs on ITO, passivate the perovskite layer, and function as conduits to facilitate hole transfer, thus significantly boosting the performance of PSCs. The champion inverted PSC employing AC-5 SAM achieves an impressive solar efficiency of 23.19 % with a high fill factor of 84.05 %. This work presents a novel molecular engineering strategy for functionalizing SAMs to tune the energy levels, molecular dipoles, packing orientations to achieve stable and efficient solar performance. Importantly, our comprehensive investigation has unraveled the associated mechanisms, offering valuable insights for future advancements in PSCs. 相似文献
997.
Mengjiao Zhuansun Yue Liu Ruihu Lu Fan Zeng Zhanyou Xu Ying Wang Prof. Yaoyue Yang Prof. Ziyun Wang Prof. Gengfeng Zheng Prof. Yuhang Wang 《Angewandte Chemie (International ed. in English)》2023,62(41):e202309875
Advancing the performance of the Cu-catalyzed electrochemical CO2 reduction reaction (CO2RR) is crucial for its practical applications. Still, the wettable pristine Cu surface often suffers from low exposure to CO2, reducing the Faradaic efficiencies (FEs) and current densities for multi-carbon (C2+) products. Recent studies have proposed that increasing surface availability for CO2 by cation-exchange ionomers can enhance the C2+ product formation rates. However, due to the rapid formation and consumption of *CO, such promotion in reaction kinetics can shorten the residence of *CO whose adsorption determines C2+ selectivity, and thus the resulting C2+ FEs remain low. Herein, we discover that the electro-kinetic retardation caused by the strong hydrophobicity of quaternary ammonium group-functionalized polynorbornene ionomers can greatly prolong the *CO residence on Cu. This unconventional electro-kinetic effect is demonstrated by the increased Tafel slopes and the decreased sensitivity of *CO coverage change to potentials. As a result, the strongly hydrophobic Cu electrodes exhibit C2+ Faradaic efficiencies of ≈90 % at a partial current density of 223 mA cm−2, more than twice of bare or hydrophilic Cu surfaces. 相似文献
998.
Yunpeng Zhong Xuesong Xie Prof. Zhiyuan Zeng Prof. Bingan Lu Prof. Gen Chen Prof. Jiang Zhou 《Angewandte Chemie (International ed. in English)》2023,62(40):e202310577
Aqueous rechargeable zinc-ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple-functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H2O is inhibited by reconstructing hydrogen bonds due to the strong interaction between TMS and H2O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn2+ ultimately to achieve a novel solvent co-intercalation ((Zn-TMS)2+) mechanism, and the intercalated TMS works as a “pillar” that provides more zincophilic sites and stabilizes the structure of cathode (NH4V4O10, (NVO)). Consequently, the Zn||NVO battery exhibits a remarkably high specific capacity of 515.6 mAh g−1 at a low current density of 0.2 A g−1 for over 40 days. This multi-functional electrolytes and solvent co-intercalation mechanism will significantly propel the practical development of aqueous batteries. 相似文献
999.
Dr. Tao Ma Dr. Youxuan Ni Diantao Li Dr. Zhengtai Zha Dr. Song Jin Weijia Zhang Liqun Jia Qiong Sun Dr. Weiwei Xie Prof. Zhanliang Tao Prof. Jun Chen 《Angewandte Chemie (International ed. in English)》2023,62(43):e202310761
Despite carbonate electrolytes exhibiting good stability to sulfurized polyacrylonitrile (SPAN), their chemical incompatibility with lithium (Li) metal anode leads to poor electrochemical performance of Li||SPAN full cells. While the SPAN employs conventional ether electrolytes that suffer from the shuttle effect, leading to rapid capacity fading. Here, we tailor a dilute electrolyte based on a low solvating power ether solvent that is both compatible with SPAN and Li metal. Unlike conventional ether electrolytes, the weakly solvating ether electrolyte enables SPAN to undergo reversibly “solid–solid” conversion. It features an anion–rich solvation structure that allows for the formation of a robust cathode electrolyte interphase on the SPAN, effectively blocking the dissolution of polysulfides into the bulk electrolyte and avoiding the shuttle effect. What's more, the unique electrolyte chemistry endowed Li ions with fast electroplating kinetics and induced high reversibility Li deposition/stripping process from 25 °C to −40 °C. Based on tailored electrolyte, Li||SPAN full cells matched with high loading SPAN cathodes (≈3.6 mAh cm−2) and 50 μm Li foil can operate stably over a wide range of temperatures. Additionally, Li||SPAN pouch cell under lean electrolyte and 5 % excess Li conditions can continuously operate stably for over a month. 相似文献
1000.
Jing Cao Tong Mou Bingbao Mei Pengfei Yao Ce Han Xue Gong Ping Song Prof. Zheng Jiang Prof. Thomas Frauenheim Prof. Jianping Xiao Prof. Weilin Xu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202310973
Full understanding to the origin of the catalytic performance of a supported nanocatalyst from the points of view of both the active component and support is significant for the achievement of high performance. Herein, based on a model electrocatalyst of single-iridium-atom-doped iron (Fe)-based layered double hydroxides (LDH) for oxygen evolution reaction (OER), we reveal the first completed origin of the catalytic performance of such supported nanocatalysts. Specially, besides the activity enhancement of Ir sites by LDH support, the stability of surface Fe sites is enhanced by doped Ir sites: DFT calculation shows that the Ir sites can reduce the activity and enhance the stability of the nearby Fe sites; while further finite element simulations indicate, the stability enhancement of distant Fe sites could be attributed to the much low concentration of OER reactant (hydroxyl ions, OH−) around them induced by the much fast consumption of OH− on highly active Ir sites. These new findings about the interaction between the main active components and supports are applicable in principle to other heterogeneous nanocatalysts and provide a completed understanding to the catalytic performance of heterogeneous nanocatalysts. 相似文献