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941.
942.
Dr. Linzhou Zhuang Dr. Yi Jia Hongli Liu Zhiheng Li Dr. Mengran Li Dr. Longzhou Zhang Dr. Xin Wang Prof. Dongjiang Yang Prof. Zhonghua Zhu Prof. Xiangdong Yao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14772-14778
The oxygen vacancies of defective iron–cobalt oxide (FeCoOx-Vo) nanosheets are modified by the homogeneously distributed sulfur (S) atoms. S atoms can not only effectively stabilize oxygen vacancies (Vo), but also form the Co−S coordination with Co active site in the Vo, which can modulate the electronic structure of the active site, enabling FeCoOx-Vo-S to exhibit much superior OER activity. FeCoOx-Vo-S exhibits a mass activity of 2440.0 A g−1 at 1.5 V vs. RHE in 1.0 m KOH, 25.4 times higher than that of RuO2. The Tafel slope is as low as 21.0 mV dec−1, indicative of its excellent charge transfer rate. When FeCoOx-Vo-S (anode catalyst) is paired with the defective CoP3/Ni2P (cathode catalyst) for overall water splitting, current densities of as high as 249.0 mA cm−2 and 406.0 mA cm−2 at a cell voltage of 2.0 V and 2.3 V, respectively, can be achieved. 相似文献
943.
Danyang Feng Yangbo Dong Liangliang Zhang Dr. Xin Ge Prof. Wei Zhang Prof. Sheng Dai Prof. Zhen-An Qiao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19671-19677
The development of noble-metal-free heterogeneous catalysts is promising for selective oxidation of aromatic alcohols; however, the relatively low conversion of non-noble metal catalysts under solvent-free atmospheric conditions hinders their industrial application. Now, a holey lamellar high entropy oxide (HEO) Co0.2Ni0.2Cu0.2Mg0.2Zn0.2O material with mesoporous structure is prepared by an anchoring and merging process. The HEO has ultra-high catalytic activity for the solvent-free aerobic oxidation of benzyl alcohol. Up to 98 % conversion can be achieved in only 2 h, to our knowledge, the highest conversion of benzyl alcohol by oxidation to date. By regulating the catalytic reaction parameters, benzoic acid or benzaldehyde can be selectively optimized as the main product. Analytical characterizations and calculations provide a deeper insight into the catalysis mechanism, revealing abundant oxygen vacancies and holey lamellar framework contribute to the ultra-high catalytic activity. 相似文献
944.
Dr. Xueting Pan Dr. Weiwei Wang Dr. Zhijun Huang Shuang Liu Juan Guo Fengrong Zhang Hongjun Yuan Xin Li Prof. Fengyong Liu Prof. Huiyu Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13659-13663
The high reactive oxygen species (ROS) generation ability and simple construction of sonosensitizer systems remain challenging in sonodynamic therapy against the hypoxic tumor. In this work, we rationally prepared MOF-derived double-layer hollow manganese silicate nanoparticle (DHMS) with highly effective ROS yield under ultrasound irradiation for multimodal imaging-guided sonodynamic therapy (SDT). The presence of Mn in DHMS increased ROS generation efficiency because it could be oxidized by holes to improve the electron–hole separation. Moreover, DHMS could produce oxygen in the tumor microenvironment, which helps overcome the hypoxia of the solid tumor and thus enhance the treatment efficiency. In vivo experiments demonstrated efficient tumor inhibition in DHMS-mediated SDT guided by ultrasound and magnetic resonance imaging. This work presents a MOF-derived nanoparticle with sonosensitive and oxygen generating ability, which provides a promising strategy for tumor hypoxia in SDT. 相似文献
945.
Dr. Qunping Fan Dr. Wenyan Su Dr. Shanshan Chen Dr. Tao Liu Dr. Wenliu Zhuang Dr. Ruijie Ma Xin Wen Dr. Zhihong Yin Dr. Zhenghui Luo Prof. Xia Guo Prof. Lintao Hou Prof. Kasper Moth-Poulsen Prof. Yu Li Prof. Zhiguo Zhang Prof. Changduk Yang Dr. Donghong Yu Prof. He Yan Prof. Maojie Zhang Prof. Ergang Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20007-20012
A non-conjugated polymer acceptor PF1-TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >105 cm−1, a high LUMO level of −3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1-TS4-based all-PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1-TS4-based all-PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16-based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non-conjugated thioalkyl segments. 相似文献
946.
Yue Sun Dr. Tiandu Dong Dr. Chunxin Lu Weiwen Xin Linsen Yang Pei Liu Yongchao Qian Yuanyuan Zhao Dr. Xiang-Yu Kong Prof. Liping Wen Prof. Lei Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17576-17581
Osmotic energy, obtained through different concentrations of salt solutions, is recognized as a form of a sustainable energy source. In the past years, membranes derived from asymmetric aromatic compounds have attracted attention because of their low cost and high performance in osmotic energy conversion. The membrane formation process, charging state, functional groups, membrane thickness, and the ion-exchange capacity of the membrane could affect the power generation performance. Among asymmetric membranes, a bipolar membrane could largely promote the ion transport. Here, two polymers with the same poly(ether sulfone) main chain but opposite charges were synthesized to prepare bipolar membranes by a nonsolvent-induced phase separation (NIPS) and spin-coating (SC) method. The maximum power density of the bipolar membrane reaches about 6.2 W m−2 under a 50-fold salinity gradient, and this result can serve as a reference for the design of bipolar membranes for osmotic energy conversion systems. 相似文献
947.
Jiaxi Zhang Longhai Zhang Li Du Huolin L. Xin John B. Goodenough Zhiming Cui 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17641-17646
A group of newly reported antiperovskite nitrides CuxIn1−xNNi3 (0≤x≤1) with tunable composition are employed as electrocatalysts for the hydrogen evolution reaction (HER). Cu0.4In0.6NNi3 shows the highest intrinsic performance among all developed catalysts with an overpotential of merely 42 mV at 10 mA cmgeo−2. Stability tests at a high current density of 100 mA cmgeo−2 show its super-stable performance with only 7 mV increase in overpotential after more than 60 hours of measurement, surpassing commercial Pt/C (increase of 170 mV). By partial substitution, the derived antiperovskite nitride achieves a smaller kinetic barrier of water dissociation compared to the unsubstituted InNNi3 and CuNNi3, revealed by first-principle calculations. It is found that the partially substituted CuxIn1−xNNi3 possesses a thermal neutral and desirable Gibbs free energy of hydrogen for HER, ascribed to the tailoring of the energy of d-band center arose by the A-site (A=Cu or In) substitution and a resulting optimization of adsorbate interactions. 相似文献
948.
Dr. Jiong Wang Dr. Xiang Huang Dr. Shibo Xi Prof. Dr. Hu Xu Prof. Dr. Xin Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(43):19324-19329
Efficient electron communication between molecular catalyst and support is critical for heterogeneous molecular electrocatalysis and yet it is often overlooked during the catalyst design. Taking CO2 electro-reduction on tetraphenylporphyrin cobalt (PCo) immobilized onto graphene as an example, we demonstrate that adding a relay molecule improves the interfacial electron communication. While the directly immobilized PCo on graphene exhibits relatively poor electron communications, it is found that diphenyl sulfide serves as an axial ligand for PCo and it improves the redox activity of PCo on the graphene surface to facilitate the generation of [PCo].- active sites for CO2 reduction. Thus, the turnover frequencies of the immobilized Co complexes are increased. Systematic structural analysis indicates that the benzene rings of diphenyl sulfide exhibit strong face-to-face stacking with graphene, which is proposed as an efficient medium to facilitate the interfacial electron communication. 相似文献
949.
Xu Feifan Wei Wei Zhang Chao Li Huawei Jing Peng Li Xin Wei Min Yu Danrui Zhang Yong Zhu Quanyao 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):697-703
Journal of Radioanalytical and Nuclear Chemistry - Controlling heat accumulation is one of the major challenges for block materials synthesizing via bulk polymerization. In the paper, cross-linked... 相似文献
950.
由于抗生素的不当使用和细菌多药耐药的出现, 迫切需要开发新的抗菌剂. 本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh3 NPs). SP-PPh3 NPs的光热转化效率为43.8%. 带正电荷的SP-PPh3 NPs可以附着在细菌上, 有助于将热量有效传递给细菌. 在热和正电荷的协同作用下, SP-PPh3 NPs对革兰氏阴性大肠杆菌(E. coli)和革兰氏阳性金黄色葡萄球菌(S. aureus)均具有抗菌活性, 其对二者的体外抑菌率分别为99.9%和98.6%. 此外, SP-PPh3 NPs具有良好的生物相容性, 对小鼠的主要器官几乎无副作用. 对细菌感染的小鼠皮肤伤口用SP-PPh3 NPs治疗12 d后, 伤口可以很好地愈合. 相似文献