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991.
Yuhang Dai Chengyi Zhang Wei Zhang Lianmeng Cui Chumei Ye Xufeng Hong Jinghao Li Ruwei Chen Wei Zong Xuan Gao Jiexin Zhu Peie Jiang Qinyou An Prof. Dan J. L. Brett Prof. Ivan P. Parkin Dr. Guanjie He Prof. Liqiang Mai 《Angewandte Chemie (International ed. in English)》2023,62(18):e202301192
Routine electrolyte additives are not effective enough for uniform zinc (Zn) deposition, because they are hard to proactively guide atomic-level Zn deposition. Here, based on underpotential deposition (UPD), we propose an “escort effect” of electrolyte additives for uniform Zn deposition at the atomic level. With nickel ion (Ni2+) additives, we found that metallic Ni deposits preferentially and triggers the UPD of Zn on Ni. This facilitates firm nucleation and uniform growth of Zn while suppressing side reactions. Besides, Ni dissolves back into the electrolyte after Zn stripping with no influence on interfacial charge transfer resistance. Consequently, the optimized cell operates for over 900 h at 1 mA cm−2 (more than 4 times longer than the blank one). Moreover, the universality of “escort effect” is identified by using Cr3+ and Co2+ additives. This work would inspire a wide range of atomic-level principles by controlling interfacial electrochemistry for various metal batteries. 相似文献
992.
Fengshu Cao Haobing Wang Nong Lu Prof. Pingyu Zhang Prof. Huaiyi Huang 《Angewandte Chemie (International ed. in English)》2023,62(14):e202301344
The photoisomerization-induced cytotoxicity in photopharmacology provides a unique pathway for phototherapy because it is independent of endogenous oxygen. In this study, we developed a biosafe photoisomerizable zinc(II) complex ( Zn1 ), which releases its trans ligand ( trans -L1 ) after being irradiated with blue light. This causes the complex to undergo photoisomerization and produce the toxic cis product ( cis -L1 ) and generate singlet oxygen (1O2). The resulting series of events caused impressive phototoxicity in hypoxic A431 skin cancer cells, as well as in a tumor model in vivo. Interestingly, Zn1 was able to inhibit tumor microtubule polymerization, while still showing good biocompatibility and biosafety in vivo. This photoisomerizable zinc(II) complex provides a novel strategy for addressing the oxygen-dependent limitation of traditional photodynamic therapy. 相似文献
993.
Xiayue Fan Rui Zhang Simi Sui Xiaorui Liu Jie Liu Chunsheng Shi Naiqin Zhao Cheng Zhong Wenbin Hu 《Angewandte Chemie (International ed. in English)》2023,62(22):e202302640
The advent of wearable electronics has strongly stimulated advanced research into the exploration of flexible zinc−air batteries (ZABs) with high theoretical energy density, high inherent safety, and low cost. However, the half-open battery structure and the high concentration of alkaline aqueous environment pose great challenges on the electrolyte retention capability and the zinc anode stability. Herein, a starch-based superabsorbent hydrogel polymer electrolyte (SSHPE) with high ionic conductivity, electrolyte absorption and retention capabilities, strong alkaline resistance and high zinc anode stability has been designed and applied in ZABs. Experimental and calculational analyses probe into the root of the superiority of SSHPEs, confirming the significance of the carboxyl functional groups along their polymer chains. These features endow the as-fabricated ZAB a long cycle life of 300 h, much longer than that with commonly used poly(vinyl alcohol)-based electrolyte. 相似文献
994.
Rong Zhang Hu Hong Xinghui Liu Shaoce Zhang Chuan Li Huilin Cui Yanbo Wang Jiahua Liu Yue Hou Pei Li Zhaodong Huang Ying Guo Chunyi Zhi 《Angewandte Chemie (International ed. in English)》2023,62(48):e202309930
Metal–organic framework-based materials are promising single-site catalysts for electrocatalytic nitrate (NO3−) reduction to value-added ammonia (NH3) on account of well-defined structures and functional tunability but still lack a molecular-level understanding for designing the high-efficient catalysts. Here, we proposed a molecular engineering strategy to enhance electrochemical NO3−-to-NH3 conversion by introducing the carbonyl groups into 1,2,4,5-tetraaminobenzene (BTA) based metal-organic polymer to precisely modulate the electronic state of metal centers. Due to the electron-withdrawing properties of the carbonyl group, metal centers can be converted to an electron-deficient state, fascinating the NO3− adsorption and promoting continuous hydrogenation reactions to produce NH3. Compared to CuBTA with a low NO3−-to-NH3 conversion efficiency of 85.1 %, quinone group functionalization endows the resulting copper tetraminobenzoquinone (CuTABQ) distinguished performance with a much higher NH3 FE of 97.7 %. This molecular engineering strategy is also universal, as verified by the improved NO3−-to-NH3 conversion performance on different metal centers, including Co and Ni. Furthermore, the assembled rechargeable Zn−NO3− battery based on CuTABQ cathode can deliver a high power density of 12.3 mW cm−2. This work provides advanced insights into the rational design of metal complex catalysts through the molecular-level regulation for NO3− electroreduction to value-added NH3. 相似文献
995.
Qianyao Fang Wuke Wei Chengcai Wu Prof. Dr. Xin Su Prof. Dr. Suli Wu 《欧洲无机化学杂志》2023,26(1):e202200486
In this work, we demonstrate a new two-step method for preparing monodisperse ZnS colloidal spheres. The method contains a hot-injection step for making primary particles as seeds and a heating-up step for aggregation growth of secondary colloidal spheres. Instead of the most commonly used thioacetamide in previous studies, thiourea (TU) was selected as the sulfur source. The temperature-dependent thermal decomposition rate of TU makes the releasing of S2− and nucleation of ZnS under proper kinetic control, meanwhile making the reaction a mild and acid-free process. By separating the two steps and using a milder sulfur precursor, monodisperse ZnS colloidal spheres have been prepared. Their diameters can be delicately tuned in the range from 54 to 172 nm through simply changing the amount of Zn and S precursor. The optical properties of the obtained ZnS spheres were studied by extinction and PL measurements, and they exhibit size-dependent optical behavior. 相似文献
996.
A zinc(II)porphyrin-based ion porous organic polymer (ZnTPyPBr4-iPOP) is successfully synthesized from newly designed pyridinium-functionalized cationic Zn-porphyrin monomer (ZnTPyPBr4) by free radical self-polymerization, and is employed as an efficient bifunctional heterogeneous catalyst for CO2 cycloaddition reaction with epoxides. The ZnTPyPBr4-iPOP exhibits excellent catalytic performance and good substrate expansion in CO2 cycloaddition reaction under solvent-free and cocatalyst-free conditions with a TOF as high as 15,500 h−1 for the cycloaddition of CO2 and epichlorohydrin. The synergistic effect of zinc(II)porphyrin as the Lewis acidic site and the Br− anion as the nucleophile in ZnTPyPBr4-iPOP responds to the high catalytic activity. Moreover, ZnTPyPBr4-iPOP can easily be recovered and reused at least seven times without the loss of activity. This work provides a valuable approach for the synthesis of novel and efficient heterogeneous catalyst for CO2 cycloaddition. 相似文献
997.
Ling Bai Yujie Li Jun Zhao Yunkai Bao Lifei Ji Jianying Dai Huilan Shi Prof. Fengchun Yang Prof. Xin Zhang 《ChemCatChem》2019,11(9):2283-2287
In this communication, the urchin-like Te template is obtained by photo-assisted electro-deposition to replace trace platinum, gold and rhodium to obtain the Pt@Te-PsS, Au@Te-PsS and Rh@Te-PsS catalysts in pursuit of their highly efficient utilization. The three-dimensional structure of urchin-like Te can not only accelerate the interface charge transfer, but also enhance the structural stability of the catalysts. Moreover, the electrons of Te are delocalized, to increase the electron density of interface and promote the hydrogen evolution reaction. Especially, the Pt@Te-PsS catalyst with the Pt loading of only 1.08 wt % exhibits extremely outstanding electrocatalytic hydrogen evolution reaction activity. The finer hierarchical structure of Te template boosts the high HER performance with low precious metal loading, which highlights a new strategy for development of high-efficiency electrocatalysts. 相似文献
998.
Pia Vervoorts Claire L. Hobday Michael G. Ehrenreich Dominik Daisenberger Gregor Kieslich 《无机化学与普通化学杂志》2019,645(15):970-974
The zeolitic imidazolate framework ZIF‐4 has recently been shown to exhibit large structural flexibility as a response to hydrostatic pressures, going from an open pore phase ( ZIF ‐ 4 ( Zn )‐ op ) to a closed pore phase ( ZIF ‐ 4 ( Zn )‐ cp ). The use of diamond anvil cell (DAC) setups has so far restricted thorough experimental insight into the evolution of lattice parameters at pressures below p < 0.1 GPa. Here we revisit the high‐pressure properties of ZIF‐4(Zn) by applying a new high‐pressure powder X‐ray diffraction setup that allows for tracking the evolution of lattice parameters in pressure increments as small as Δp = 0.005 GPa in the pressure range p = ambient – 0.4 GPa; a pressure resolution that cannot be achieved by using traditional DACs. We find ZIF‐4(Zn) has a bulk modulus of K( ZIF ‐ 4 ( Zn )‐ op ) = 2.01 ± 0.05 GPa and K( ZIF ‐ 4 ( Zn )‐ cp ) = 4.39 ± 0.20 GPa, clarifying and confirming some ambiguous results that have been reported previously. 相似文献
999.
《无机化学与普通化学杂志》2018,644(6):357-366
Two cadmium(II) and two zinc(II) coordination complexes with diverse structural motifs, [Cd2(HL)I3H2O] · H2O ( 1 ), [Cd2(H2L)2(H2O)4] · 2SO4 · 14H2O ( 2 ), [Zn3(L′)2(H2O)6] · 4H2O · 2(NO3) ( 3 ), and [Zn3L'2(H2O)2Cl2] · H2O ( 4 ) [H2L = 1,1‐bis(5‐(pyrid‐2‐yl)‐1,2,4‐triazol‐3‐yl)methane; H2L′ = 1,1‐bis(5‐(pyrid‐2‐yl)‐1,2,4‐triazol‐3‐yl)methanone] were synthesized through a hydrothermal method. These coordination complexes were characterized by single‐crystal X‐ray diffraction, powder X‐ray diffraction (PXRD), FT‐IR spectroscopy, and photo‐luminescent experiments. Single crystal structural analysis revealed that 1 – 4 belong to polynuclear coordination compounds. PXRD analysis of 1 – 4 unambiguously confirmed the purity of the as‐synthesized coordination compounds. It is the first time to synthesize coordination compounds based on H2L′, which reacted from the original material H2L through in‐situ hydrothermal conditions. In addition, photo‐luminescent experiments revealed that 1 – 4 have real‐time sensing effects for benzaldehyde through fluorescence quenching. For 1 – 4 , the photo‐luminescent quenching effect for benzaldehyde was also compared and the coordination complexes 3 and 4 based on H2L′ have higher photo‐luminescent quenching effect than compounds 1 and 2 . 相似文献
1000.
The thermal behaviour of a mixture containing an ammonium polyphosphate based compound (AP760) and zinc borate (ZB) is investigated. After an investigation of the degradation of the pure components, the interactions between them are examined by thermogravimetry. Then, X-ray diffraction (XRD) and 11B and 31P solid-state nuclear magnetic resonance (NMR) measurements have been carried out on residues of mixtures of AP760 and FBZB heat treated at different characteristic temperatures. It reveals the nature of the interactions taking place between the two components. It is demonstrated that reactions lead to the formation of zinc phosphate and of borophosphates. Mechanisms of thermal degradation are proposed. 相似文献