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31.
《中国化学快报》2023,34(9):108157
This work reported the lanthanide ion (Gd3+) doped tungsten trioxide (Gd-WO3) nanocrystal for remarkable promoted photocatalytic degradation of organic pollutants and simultaneous in-situ H2O2 production. With doped lanthanide ion (Gd3+), Gd-WO3 showed a much broad and enhanced solar light absorption, which not only promoted the photocatalytic degradation efficiency of organic compounds, but also provided a suitable bandgap for direct reduction of oxygen to H2O2. Additionally, the isolated Gd3+ on WO3 surface can efficiently weaken the *OOH binding energy, increasing the activity and selectivity of direct reduction of oxygen to H2O2, with a rate of 0.58 mmol L−1 g−1 h−1. The in-situ generated H2O2 can be subsequently converted to •OH based on Fenton reaction, further contributed to the overall removal of organic pollutants. Our results demonstrate a cascade photocatalytic oxidation-Fenton reaction which can efficiently utilize photo-generated electrons and holes for organic pollutants treatment. 相似文献
32.
Lifeng Wang Naiqing Ren Dr. Yu Yao Dr. Hai Yang Dr. Wei Jiang Zixu He Dr. Yang Jiang Prof. Shuhong Jiao Prof. Li Song Prof. Xiaojun Wu Prof. Zhong-Shuai Wu Prof. Yan Yu 《Angewandte Chemie (International ed. in English)》2023,62(6):e202214372
Metallic Na is a promising metal anode for large-scale energy storage. Nevertheless, unstable solid electrolyte interphase (SEI) and uncontrollable Na dendrite growth lead to disastrous short circuit and poor cycle life. Through phase field and ab initio molecular dynamics simulation, we first predict that the sodium bromide (NaBr) with the lowest Na ion diffusion energy barrier among sodium halogen compounds (NaX, X=F, Cl, Br, I) is the ideal SEI composition to induce the spherical Na deposition for suppressing dendrite growth. Then, 1,2-dibromobenzene (1,2-DBB) additive is introduced into the common fluoroethylene carbonate-based carbonate electrolyte (the corresponding SEI has high mechanical stability) to construct a desirable NaBr-rich stable SEI layer. When the Na||Na3V2(PO4)3 cell utilizes the electrolyte with 1,2-DBB additive, an extraordinary capacity retention of 94 % is achieved after 2000 cycles at a high rate of 10 C. This study provides a design philosophy for dendrite-free Na metal anode and can be expanded to other metal anodes. 相似文献
33.
Xinyao Wang Dr. Xiaowei Yang Chen Zhao Yutong Pi Prof. Xiaobo Li Prof. Zhongfan Jia Prof. Si Zhou Prof. Jijun Zhao Prof. Limin Wu Prof. Jian Liu 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302829
Rational design of polymer structures at the molecular level promotes the iteration of high-performance photocatalyst for sustainable photocatalytic hydrogen peroxide (H2O2) production from oxygen and water, which also lays the basis for revealing the reaction mechanism. Here we report a benzoxazine-based m-aminophenol-formaldehyde resin (APFac) polymerized at ambient conditions, exhibiting superior H2O2 yield and long-term stability to most polymeric photocatalysts. Benzoxazine structure was identified as the crucial photocatalytic active segment in APFac. Favorable adsorption of oxygen/intermediates on benzoxazine structure and commendable product selectivity accelerated the reaction kinetically in stepwise single-electron oxygen reduction reaction. The proposed benzoxazine-based phenolic resin provides the possibility of production in batches and industrial application, and sheds light on the de novo design and analysis of metal-free polymeric photocatalysts. 相似文献
34.
Min Wang Huimin Chen Min Wang Jinxiu Wang Dr. Yongxiao Tuo Prof. Wenzhen Li Shanshan Zhou Linghui Kong Prof. Guangbo Liu Prof. Luhua Jiang Guoxiong Wang 《Angewandte Chemie (International ed. in English)》2023,62(40):e202306456
Heterostructured oxides with versatile active sites, as a class of efficient catalysts for CO2 electrochemical reduction (CO2ER), are prone to undergo structure reconstruction under working conditions, thus bringing challenges to understanding the reaction mechanism and rationally designing catalysts. Herein, we for the first time elucidate the structural reconstruction of CuO/SnO2 under electrochemical potentials and reveal the intrinsic relationship between CO2ER product selectivity and the in situ evolved heterostructures. At −0.85 VRHE, the CuO/SnO2 evolves to Cu2O/SnO2 with high selectivity to HCOOH (Faradaic efficiency of 54.81 %). Mostly interestingly, it is reconstructed to Cu/SnO2-x at −1.05 VRHE with significantly improved Faradaic efficiency to ethanol of 39.8 %. In situ Raman spectra and density functional theory (DFT) calculations reveal that the synergetic absorption of *COOH and *CHOCO intermediates at the interface of Cu/SnO2-x favors the formation of *CO and decreases the energy barrier of C−C coupling, leading to high selectivity to ethanol. 相似文献
35.
Yutong Pi Linxia Cui Prof. Wenhao Luo Dr. Haitao Li Dr. Yanfu Ma Dr. Na Ta Xinyao Wang Prof. Rui Gao Prof. Dan Wang Prof. Qihua Yang Prof. Jian Liu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202307096
Mimicking the structures and functions of cells to create artificial organelles has spurred the development of efficient strategies for production of hollow nanoreactors with biomimetic catalytic functions. However, such structure are challenging to fabricate and are thus rarely reported. We report the design of hollow nanoreactors with hollow multishelled structure (HoMS) and spatially loaded metal nanoparticles. Starting from a molecular-level design strategy, well-defined hollow multishelled structure phenolic resins (HoMS-PR) and carbon (HoMS-C) submicron particles were accurately constructed. HoMS-C serves as an excellent, versatile platform, owing to its tunable properties with tailored functional sites for achieving precise spatial location of metal nanoparticles, internally encapsulated (Pd@HoMS-C) or externally supported (Pd/HoMS-C). Impressively, the combination of the delicate nanoarchitecture and spatially loaded metal nanoparticles endow the pair of nanoreactors with size–shape-selective molecular recognition properties in catalytic semihydrogenation, including high activity and selectivity of Pd@HoMS-C for small aliphatic substrates and Pd/HoMS-C for large aromatic substrates. Theoretical calculations provide insight into the pair of nanoreactors with distinct behaviors due to the differences in energy barrier of substrate adsorption. This work provides guidance on the rational design and accurate construction of hollow nanoreactors with precisely located active sites and a finely modulated microenvironment by mimicking the functions of cells. 相似文献
36.
Xiang-Zhu Wei Tian-Yu Ding Dr. Yang Wang Dr. Bing Yang Dr. Qing-Qing Yang Prof. Dr. Shengfa Ye Prof. Dr. Chen-Ho Tung Prof. Dr. Li-Zhu Wu 《Angewandte Chemie (International ed. in English)》2023,62(36):e202308192
High-valent iron-oxo species are appealing for conducting O−O bond formation for water oxidation reactions. However, their high reactivity poses a great challenge to the dissection of their chemical transformations. Herein, we introduce an electron-rich and oxidation-resistant ligand, 2-[(2,2′-bipyridin)-6-yl]propan-2-ol to stabilize such fleeting intermediates. Advanced spectroscopies and electrochemical studies demonstrate a high-valent FeV(O) species formation in water. Combining kinetic and oxygen isotope labelling experiments and organic reactions indicates that the FeV(O) species is responsible for O−O bond formation via water nucleophilic attack under the real catalytic water oxidation conditions. 相似文献
37.
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
38.
Qingchun Xu Puning Ren Yang Peng Prof. Nengchao Luo Zhuyan Gao Caixia Meng Jian Zhang Prof. Feng Wang 《Angewandte Chemie (International ed. in English)》2023,62(30):e202301668
Photocatalytic 2-iodoethanol (IEO) coupling provides 1,4-butanediol (BDO) of particular interest to produce degradable polyesters. However, the reduction potential of IEO is too negative (−1.9 vs NHE) to be satisfied by most of the semiconductors, and the kinetics of transferring one electron for IEO coupling is slow. Here we design a catalytic Ni complex, which works synergistically with TiO2, realizing reductive coupling of IEO powered by photo-energy. Coordinating by terpyridine stabilizes Ni2+ from being photo-deposited to TiO2, thereby retaining the steric configuration beneficial for IEO coupling. The Ni complex can rapidly extract electrons from TiO2, generating a low-valent Ni capable of reducing IEO. The photocatalytic IEO coupling thus provides BDO in 72 % selectivity. By a stepwise procedure, BDO is obtained with 70 % selectivity from ethylene glycol. This work put forward a strategy for the photocatalytic reduction of molecules requiring strong negative potential. 相似文献
39.
Dr. Yang Yu Jintao Wang Zhaoxian Qin Yingtong Lv Qijun Pei Khai Chen Tan Prof. Tengfei Zhang Dr. Anan Wu Prof. Teng He Dr. Hui Wu Dr. Andrew S. Lipton Prof. Ping Chen 《Angewandte Chemie (International ed. in English)》2023,62(26):e202302679
Replacing widely used organic liquid electrolytes with solid-state electrolytes (SSEs) could effectively solve the safety issues in sodium-ion batteries. Efforts on seeking novel solid-state electrolytes have been continued for decades. However, issues about SSEs still exist, such as low ionic conductivity at ambient temperature, difficulty in manufacturing, low electrochemical stability, poor compatibility with electrodes, etc. Here, sodium carbazolide (Na-CZ) and its THF-coordinated derivatives are rationally fabricated as Na+ conductors, and two of their crystal structures are successfully solved. Among these materials, THF-coordinated complexes exhibit fast Na+ conductivities, i.e., 1.20×10−4 S cm−1 and 1.95×10−3 S cm−1 at 90 °C for Na-CZ-1THF and Na-CZ-2THF, respectively, which are among the top Na+ conductors under the same condition. Furthermore, stable Na plating/stripping is observed even over 400 h cycling, showing outstanding interfacial stability and compatibility against Na electrode. More advantages such as ease of synthesis, low-cost, and cold pressing for molding can be obtained. In situ NMR results revealed that the evaporation of THF may play an essential role in the Na+ migration, where the movement of THF creates defects/vacancies and facilitates the migration of Na+. 相似文献
40.
Hui Luo Dr. Kejun Bu Dr. Yanfeng Yin Dong Wang Cuimi Shi Songhao Guo Tonghuan Fu Jiayuan Liang Bingyan Liu Dr. Dongzhou Zhang Prof. Liang-Jin Xu Prof. Qingyang Hu Prof. Yang Ding Prof. Shengye Jin Prof. Wenge Yang Prof. Biwu Ma Prof. Xujie Lü 《Angewandte Chemie (International ed. in English)》2023,62(37):e202304494
Low-dimensional (low-D) organic metal halide hybrids (OMHHs) have emerged as fascinating candidates for optoelectronics due to their integrated properties from both organic and inorganic components. However, for most of low-D OMHHs, especially the zero-D (0D) compounds, the inferior electronic coupling between organic ligands and inorganic metal halides prevents efficient charge transfer at the hybrid interfaces and thus limits their further tunability of optical and electronic properties. Here, using pressure to regulate the interfacial interactions, efficient charge transfer from organic ligands to metal halides is achieved, which leads to a near-unity photoluminescence quantum yield (PLQY) at around 6.0 GPa in a 0D OMHH, [(C6H5)4P]2SbCl5. In situ experimental characterizations and theoretical simulations reveal that the pressure-induced electronic coupling between the lone-pair electrons of Sb3+ and the π electrons of benzene ring (lp-π interaction) serves as an unexpected “bridge” for the charge transfer. Our work opens a versatile strategy for the new materials design by manipulating the lp-π interactions in organic–inorganic hybrid systems. 相似文献