TETRAHEDRON
·
2023
·
IF 2.1
Yi Liu,Weilu Ding,Yongzhen Li,Ming Li,Ying Liu,Yunong Li,Qian Su,Zifeng Yang
In this work, we designed a novel thermally stable Zn bromide-based deep eutectic ionic liquid (DEIL), synthesized from tetralkylphosphonium bromide (Bu 4 PBr) and ZnBr 2 by a facile heating method. The structural changes and the physical properties of the catalyst were in-depth investigated. Among all the DEILs, ZnBr 2 ·2Bu 4 PBr showed high activity, achieved 98.2% propylene carbonate (PC) yield at a low catalyst usage (0.15 mol%), and remained good stabilities for 8 cycles. Furthermore, based on experimental results and DFT calculations, we found that Bu 4 P + cation of DEIL served as a frame charge-balanced species interacting with three possible anions of ZnBr 4 2− , ZnBr 3 − and Br − . The interaction is accompanied by a reversible pre-equilibrium in which [Bu 4 P] 2 [ZnBr 4 ] could dissociate and produce the true catalytically active species, [Bu 4 P][ZnBr 3 ] and Bu 4 PBr. Meanwhile, a possible ring-opening mechanism was proposed, in which the synergetic effect of cations and anions in the catalytic system can promote ring-opening. The significance of this study is that it provides guidance for developing metal bromide-based DEILs for carbonate synthesis.
研究领域:
化学工程
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催化
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绿色化学
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材料科学
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DOI
高影响因子
GREEN CHEMISTRY
·
2023
·Vol. 25
·期 7
·2596-2607
·
IF 9.8
Yudi Wang,Jia Kou,Xuewei Wang,Xi Chen
Chitin hydrolysis is an important but challenging reaction for shell biorefineries. In this study, we devised a mild aging-hydrolysis integrated approach to selectively produce N-acetyl-D-glucosamine (NAG) from chitin in cheap and abundant CaCl2-based molten salt hydrate solvents (MSHs). The acid-aged chitin could be directly employed and hydrolyzed in 50 wt% CaCl2 solution at 393 K for 1 h, producing NAG in 51.0% yield, which was further improved to 66.8% with the addition of ZnBr2 (10 wt%) as a co-salt. The synergy of aging and the CaCl2 MSHs was critical for the efficient chitin hydrolysis. A significant decrease of chitin's molecular weight was observed after aging at near room temperature, while the CaCl2 MSHs enabled chitin swelling and dissolution to facilitate the substantial cleavage of glycosidic bonds during the hydrolysis reaction. The combined contrast experiments, TOF-MS, XPS, and NMR studies revealed that both the Ca2+ cation and the Cl− anion have closely interacted with the chitin chains primarily by coordinating with the carbonyl oxygen/amido nitrogen atoms or by forming hydrogen bonds with the –OH groups, respectively, which could alter the electrostatic states of the chitin chains and favor the hydrolysis.
研究领域:
化学工程
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生物化学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Siyu Zhang,Hang Jiang,Siting Liu,Zhikang Zhou,Jianwei Wang,Qianyun Wang,Kedi Cai,Qinzhi Lai,Qian Wang
Zinc–bromine flow batteries (ZBFB) are gaining significant attention for large–scale energy storage due to the high energy density and affordable cost. Nevertheless, the diffusion of Br 2 and the relatively low activity of Br 2 /Br − impede their broader application. Herein, a bi–phasic rutile/anatase–TiO 2 embedded in carbon composite with hollow sphere structure (R/A–TiO 2 @HCS) is proposed as the catalyst for the Br 2 /Br − electrode. The internal electric field (IEF) formed between rutile–TiO 2 and anatase–TiO 2 regulates the adsorption capability for active bromine species. The appropriate adsorption capability can rapidly transfer the generated Br 2 complex (QBr n ) to the adsorbent component R/A–TiO 2 during charging, liberating the carbon active sites, and release QBr n back to the carbon reaction sites timely during discharging, satisfying the both adsorption and desorption requirements of QBr n in different processes. The kinetics for oxidation and reduction are simultaneously enhanced. Moreover, the hollow construction offers storage space for QBr n , relieving its penetration problem. Under the synergistical cooperation, the ZBFB assembled with R/A–TiO 2 @HCS demonstrates the energy efficiency (EE) of 83.6 % at 80 mA cm −2 , without significant decay over 500 cycles. And the EE still maintains 70.0 % even under 160 mA cm −2 . This work highlights the significance of tailored electrocatalyst for ZBFB.
研究领域:
电化学
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材料科学
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能源存储
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产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2024
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IF 8.1
Qiming Zhang,Hang Jiang,Siting Liu,Qianyun Wang,Jianwei Wang,Zhikang Zhou,Kedi Cai,Qinzhi Lai,Qian Wang
Zinc-bromine flow batteries (ZBFBs) are considered as one of the most promising energy storage technologies, owing to the high energy density and low cost. However, the sluggish electrochemical kinetics and severe self-discharge lead to the limited power density and service life, hindering the practical application of ZBFBs. Herein, Prussian blue modified nitrogen-doped carbon (PB@NC) is synthesized as an auxiliary redox-targeting catalyst for the bromine cathode. The excellent conductivity and adsorption capability of nitrogen-doped carbon (NC) ensure the smooth electron transfer and the enriched bromine species at the reaction interface. Under the assistance of NC, Prussian blue (PB) could rapidly lose or gain electrons, then transform into the oxidized or reduced states that subsequently engages in the targeted redox reactions with the contacted Br ‐ or Br 2 . It offers an alternative reaction pathway for the bromine redox, promoting the electrochemical kinetics significantly, which demonstrates a reversible redox-targeting catalytic effect. Therefore, a ZBFB modified with PB@NC achieves an energy efficiency of 85.9% at a current density of 80 mA cm −2 , and ultra-high energy efficiency of 71.1% even at current density of 160 mA cm −2 . This work offers a promising strategy for advancing the development of ZBFBs by the efficient cathode material design.
研究领域:
材料科学
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电化学
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能源存储技术
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产品关联
DOI
高影响因子
Catalysts
·
2024
·Vol. 14
·期 1
·41
·
IF 3.8
Huajun Wang,Jingjing Ma
A series of Zn salts were used as catalysts for the reaction of glycerol and urea to produce glycerol carbonate and it was found that ZnSO4showed the highest catalytic activity. Furthermore, the effects of reaction parameters on the glycerol conversion and glycerol carbonate yield were studied in detail. The results indicated that the glycerol conversion and glycerol carbonate yield were increased with the reaction temperature, reaction time, and catalyst amount while the optimal reaction conditions were 140 °C, 240 min, catalyst amount of 5 wt% (based on the glycerol weight), and urea-to-glycerol molar ratio of 1.1:1. During the reaction, the ZnSO4catalyst is transformed into Zn(NH3)2SO4at the initial stage of the reaction and then further transformed into Zn(C3H6O3). Zn(C3H6O3) and (NH4)2SO4may be the true active species for the activation of urea and glycerol, respectively. The reaction mechanism is proposed in this article. Based on the experimental results, a reaction kinetics model considering the change in volume of the reaction system was also established, and the model parameters were obtained by fitting the experimental data. The statistical results showed that the established kinetics model is accurate.Keywords:glycerol;urea;glycerol carbonate;zinc sulfate;reaction kinetics
研究领域:
化学工程
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催化
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有机化学
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产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Keqiang Chen,Dan Liu,Weiqi Lu,Kaihuai Zhuo,Guogang Li
Shelling with chalcogenides on the surface of lead halide perovskite (LHP) nanocrystals (NCs) is believed to be an effective approach to increase their stability under high-moisture/aqueous conditions, which is important for LHP NC-based optoelectronic devices. However, it is still a challenge to prepare high-quality LHP/chalcogenide core/shell NCs with moisture/aqueous stability. In this work, a surface-defect-induced strategy is carried out to facilitate the adsorption of Br– ions and subsequently Zn2+ ions to preform a bipolar surface, which reduces the energy barrier at the CsPbBr3/ZnS interface and promotes the epitaxial growth of the ZnS shell layer. The aqueous stability of the as-received NCs shows an increase of over 12 times compared to that of the original one. Likewise, Mn2+ ions are introduced to further reduce the geometric symmetry mismatch and defect density at the CsPbBr3/ZnS interface. Interestingly, aqueous stability characterizations illustrate negligible degradation even after 230 min of ultrasonication, suggesting their outstanding stability. This work proposes an effective approach to prepare high-quality LHP/chalcogenide core/shell NCs, which possess great potential in the fabrication of stable optoelectronic devices.
研究领域:
材料科学
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纳米技术
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光电子学
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化学工程
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产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Jie Hou,Jun Chen,Cheng Luo,Juntao Li,Cheng Li,Ruiling Zhang,Jianyong Liu,Peigeng Han
Zero-dimensional (0D) metal halides have emerged as excellent luminescent materials for optical and optoelectronic applications. Especially environmentally friendly ternary zinc halides have recently drawn increasing attention. Herein, we present the codoping of Cu+ and Mn2+ ions into 0D Cs2ZnBr4 single crystals (SCs), which show bright PL emission and high stability. Adjusting the Cu+/Mn2+ ratio can make the photoluminescence quantum yield (PLQY) exceed 90%, which is much higher than that of the single-ion doped sample. The efficient PL is determined by a combination of Cu+–Mn2+ competitive interaction, Cu+–Mn2+ energy transfer, and Cu+–Mn2+ synergistic passivation. More interestingly, the codoped sample shows a better scintillation performance with a low detection limit of 52 nGyair/s and a sensitive spatial resolution of 13.2 lp/mm. We further explore the promising applications of Cu+–Mn2+-codoped Cs2ZnBr4 SCs for anticounterfeiting and X-ray imaging. These results not only help to grasp the excited-state photophysical processes of 0D codoped metal halides but also provide a new way for the design and development of environmentally friendly luminescent materials.
研究领域:
材料科学
·
光学
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产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Mengqi Zhang,Jingcong Hu,Guoqiang Xi,Jie Tu,Qianqian Yang,Linhan Fan,Yue Lu,Manling Sui,Xuejiao Sun,Linxing Zhang,Jianjun Tian
Superlattices (SLs) based on colloidal nanocrystals (NCs) represent a fascinating structure with long-range and ordered NCs inside the assembled superstructures, displaying great potential application in electronic devices because of the customizable arrangement of building blocks. It is a great challenge to achieve macroscopical SL films by a solution process due to the inherent sensitivity and difficulty in controlling colloidal NCs. In this study, we propose a controllable strategy to create perovskite CsPbBr3 NC SL films through a surface in situ cross-linking reaction incorporating conjugated linoleic acid (CLA), a naturally polymerizable small molecule. CLA enables the in situ cross-linking of adjacent NCs under polarity-triggered conditions, which effectively arranges the NCs in a solid form at a molecular level to achieve fcc SL structural films. Importantly, we report for the first time NC SL films that are simultaneous with outstanding intrinsically linearly polarized emission and orderly electric polarity, which are derived from consistent dipole alignment, thus showing promising potential for application in information storage and optoelectronics. This method provides a general bottom-up approach, expanding the assembly library for fundamental studies and technological applications.
研究领域:
材料科学
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光学工程
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纳米技术
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产品关联
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
·
2024
·
IF 5.8
Yufa Gao,Wenlu Zhang,Mohammad Ali Asadollahi,Chao Liu,Guang Yu,Haiming Li,Bin Li
Clean and efficient pretreatment is a critical process for producing cellulosic sugar platform for the production of advanced biofuels and chemicals. Combining a chemical treatment with ball milling is a relatively simple and environmentally friendly procedure, which may reduce the pretreatment time and energy consumption. Hence, in this study, the mineral salts (e.g. ZnCl 2 , ZnBr 2 , LiCl, and LiBr) were used to enhance the ball milling. Firstly, microcrystalline cellulose (MCC) as a model compound of pure cellulose was pretreated by mineral salt-assisted ball milling to investigate the effect of mineral salt and ball milling for promoting cellulose saccharification. LiBr showed the best effect to improve the effectiveness of ball milling pretreatment, and the glucose yield of saccharification reached up to 93.8 % under the optimal conditions. Then, corncob residue (CCR) as a distinctive starting material was pretreated by LiBr-assisted ball milling, and the corresponding glucose yield of saccharification (48 h) with enzyme dosage of 5 FPU/g-CCR was as high as 97.4 %. Characterization verified that, the effect of LiBr and ball milling could more effectively break hydrogen bonds and crystalline structure of cellulose, thus highly promoting the followed enzymatic saccharification without lignin removal and washing after LiBr-assisted ball milling pretreatment. This work can help to understand the effect of combining mineral salt with ball milling, which is beneficial to the development of clean and effective pretreatment approach for lignocellulose biorefinery.
研究领域:
生物能源
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生物质转化
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产品关联
DOI
高影响因子
POLYHEDRON
·
2024
·
IF 2.4
Zhengwei Wu,Jiawen Bao,Hongyang Zhang,Yingying Luo,Zhonglu You
Molecular nanoclusters comprising heterometallic Ni-Zn cores are an interesting class of compounds. In this paper, five novel Ni II -Zn II complexes [Ni 2 Zn 2 ClL 3 (HL) 3 ]·0·.25H 2 O ( 1 ), [Ni 2 Zn 2 BrL 3 (HL) 3 ]·0·.25H 2 O ( 2 ), [Ni 2 Zn 2 Br 2 L 2 (N 3 ) 2 (MeOH) 2 ]·2MeOH ( 3 ), [Ni 2 Zn 2 I 2 L 2 (N 3 ) 2 (MeOH) 2 ]·2MeOH ( 4 ), and [Ni 2 Zn 2 I 2 L 2 (N 3 ) 2 (DMF) 2 ] ( 5 ), were prepared from the Schiff base 2-(3-ethoxy-2-hydroxybenzylideneamino)-4-methylphenol (H 2 L). The complexes have been characterized by elemental analysis, IR, UV–Vis spectra. Molecular structures of the complexes have been determined by single crystal X-ray determination. In complexes 1 and 2 , three of the Schiff bases coordinate to the metal atoms via ether oxygen, imino nitrogen and two phenolate oxygen atoms, while the fourth one coordinates through ether oxygen, imino nitrogen and one phenolate oxygen atoms. In complexes 3 , 4 and 5 , all the donor atoms in the Schiff base ligands participate in coordination. The Ni and Zn atoms in the complexes are in octahedral and trigonal bipyramidal coordination, respectively. The anions of the metal salts and the azide anion, as well as methanol and DMF molecules furnish the coordination sphere. The compounds were evaluated for their antibacterial activities on Bacillus subtilis , Staphylococcus aureus , Escherichia coli and Pseudomonas fluorescens , and antifungal activities on Candida albicans and Aspergillus niger . Interestingly, the complexes have effective activities against Bacillus subtilis and Staphylococcus aureus .
研究领域:
无机化学
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生物化学
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药物化学
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产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 7
·1607
·
IF 3.1
Hang Li,Jiazhen He,Xiaoqian Wang,Qi Liu,Xuemin Luo,Mingwei Wang,Jinfeng Liu,Chengqi Liu,Yong Liu
As a direct band gap semiconductor, perovskite has the advantages of high carrier mobility, long charge diffusion distance, high defect tolerance and low-cost solution preparation technology. Compared with traditional metal halide perovskites, which regulate energy band and luminescence by changing halogen, perovskite quantum dots (QDs) have a surface effect and quantum confinement effect. Based on the LaMer nucleation growth theory, we have synthesized CsPbBr3QDs with high dimensional homogeneity by creating an environment rich in Br−ions based on the general thermal injection method. Moreover, the size of the quantum dots can be adjusted by simply changing the reaction temperature and the concentration of Br−ions in the system, and the blue emission of strongly confined pure CsPbBr3perovskite is realized. Finally, optical and electrochemical tests suggested that the synthesized quantum dots have the potential to be used in the field of photocatalysis.
研究领域:
材料科学
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光电催化
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纳米技术
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产品关联
DOI
PubMed
高影响因子
Materials
·
2024
·Vol. 17
·期 11
·2563
·
IF 3.1
Qi Liu,Hang Li,Xiaoqian Wang,Jiazhen He,Xuemin Luo,Mingwei Wang,Jinfeng Liu,Yong Liu
Amidst the rapid advancements in the fields of photovoltaics and optoelectronic devices, CsPbBr3nanosheets (NSs) have emerged as a focal point of research due to their exceptional optical and electronic properties. This work explores the application potential of CsPbBr3NSs in photonic and catalytic domains. Utilizing an optimized hot-injection method and a ZnBr2-assisted in situ passivation strategy, we successfully synthesized CsPbBr3NSs with controlled dimensions and optical characteristics. Comprehensive characterization revealed that the nucleation environment and thickness significantly influenced the structure and optical performance of the materials. The results indicate that the optimized synthesis method enables control over the lateral dimensions of the nanoparticles, ranging from 9.1 ± 0.06 nm to 334.5 ± 4.40 nm, facilitating the tuning of the excitation wavelength from 460 nm (blue) to 510 nm (green). Further analyses involving photoresponse and electrochemical impedance spectroscopy demonstrated the substantial potential of these NSs in applications such as photocatalysis and energy conversion.
研究领域:
材料科学
·
光化学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）