Frontiers in Chemistry
·
2019
·
IF 3.782
Liu Peiyuan,Ling Xiaofei,Zhong Cheng,Deng Yida,Han Xiaopeng,Hu Wenbin
Zinc-air battery has drawn increasing attention from the whole world owing to its large energy capacity, stable working voltage, environmentally friendship, and low price. A special porous Zn with three-dimensional (3D) network frame structure, whose multistage average pore sizes can be tuned from 300 to 8 um, is synthesized in this work. It is found that there is a competition between Zn2+ and NH4+ for their reduction on the supports. And the decrease of Zn2+ concentration and increase of NH4+ concentration can facilitate the decrease of pore size. Potential-dynamic polarization was tested with 3-electrodes cell, aiming to characterize the electrochemical activity and corrosion properties of porous Zn and commercial Zn foil electrodes. After optimization, the porous Zn prepared with the parameters of 3 M NaBr, 1 M C2H3O2NH4, and 0.01 M C4H6O4Zn shows the most negative corrosion potential of −1.45 V among all the samples, indicating the remarkable anti-corrosion property. Its discharge specific capacity is up to 812 mAh g−1. And discharge-charge test of the porous Zn shows an initial discharge platform of 1.33 V and an initial charge platform of 1.96 V, performing a small overpotential. What's more, the porous Zn exhibits a much longer cycle life than commercial Zn foil. Our work will not only shed light on the design and synthesis of other porous metal materials, but also further promote the development of Zn-based battery electrochemistry.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
PubMed
高影响因子
Journal of CO2 Utilization
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2022
·
IF 8.321
Gaosheng Ren,Tianfu Dai,Yu Tang,Zhihui Su,Nan Xu,Weichen Du,Chengyi Dai,Xiaoxun Ma
The construction of three-dimensional hierarchical porous and hydrophobic-aerophilic interfaces facilitates mass transport and CO 2 enrichment by kinetically accelerating the CO 2 electrochemical reduction reaction (CO 2 RR). Inspired by the process of baking bread, in which pores that connect the interior of the bread to its exterior are created, we propose a template-free metal carbonate-porous metal oxide (MC-PMO) strategy to synthesize porous metal oxides with tunable pore size. Using this strategy, a series of porous metal oxides with different morphologies and different metals was successfully developed. Furthermore, the effect of catalyst mass transport on the CO 2 RR was explored. The porous catalysts with suitable pore size promoted mass transfer, which significantly enhanced the activation and transformation of CO 2 . In addition, based on a hydrophobic group-modified metal oxide surface (HG-MO) strategy, a hydrophobic-aerophilic interface microenvironment was constructed to reduce the water dissociation activity and effectively inhibit the hydrogen evolution reaction (HER). HP-ZnO-500 @ 2-NTL was obtained by modifying hierarchical porous zinc oxide (HP-ZnO-500) with the hydrophobic 2-naphthalenethiol (2-NTL). The hydrophobic surface of HP-ZnO-500 @ 2-NTL was easily enriched with CO 2 gas under the influence of the “plastron effect”, and the surface hydrophobic film stabilized the M–H bond. Thus, HER was suppressed. At − 1.0 V vs. RHE, HP-ZnO-500 @ 2-NTL achieved a faradaic efficiency of CO (FE CO ) as high as 83.0%, and displayed high catalytic activity in a wide potential range. The “MC-PMO” strategy and “HG-MO” strategy reported herein are universal and are expected to guide the further preparation and modification of different metal-based porous metal oxides for sustainable CO 2 RR.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2018
·
IF 3.716
Shujun Xia,Zhixiong Cai,Jing Dong,Shuya Wang,Yiru Wang,Huaizhi Kang,Xi Chen
In this study, porous ZnFe 2 O 4 /carbon, derived from Zn-Fe zeolitic imidazolate framework (Zn-Fe-ZIF), was employed as a novel sorbent for magnetic-assisted dispersive miniaturized solid phase extraction (M-DμSPE). The Zn-Fe-ZIF derived magnetic porous ZnFe 2 O 4 /carbon was easily prepared using a one-pot solvothermal method, and its morphology, structure and magnetic characteristics were evaluated via scanning electron microscopy, powder X-ray diffraction, Raman spectroscopy and vibrating sample magnetometry. The extraction ability of ZnFe 2 O 4 /carbon is evaluated by different kinds of compounds including organochlorine pesticides, pyrethroid insecticides, aldehydes, nerolidol, benzoic acid and sorbic acid. A M-DμSPE method was developed for the analysis of organochlorine pesticides. Several parameters affecting the extraction efficiency were systematically investigated. The calibration curves ranged from 0.05 to 100 ng g −1 and the limits of detection were 0.005–0.3 ng g −1 . The intra-day and inter-day relative standard deviations were lower than 2.3 and 5.2%. The recoveries of spiked organochlorine pesticides were in the range of 86.1–109.4%.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
GREEN CHEMISTRY
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2018
·Vol. 20
·期 4
·903-911
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IF 8.586
Jian Chen,Mingmei Zhong,Lin Tao,Lina Liu,Sanjeevi Jayakumar,Chunzhi Li,He Li,Qihua Yang
The cooperation of catalyst and co-catalyst, together with efficient recycling, is one of the most important and still big challenges for CO2 cycloaddition reaction. Herein, we report a facile and atom-efficient method to synthesize a porous zinc-porphyrin-based framework (P-POF-Zn) as a catalyst for the synthesis of cyclic carbonates. It was demonstrated for the first time that the combination of P-POF-Zn and thermal-responsive ionic liquid [CPeDMAPy]Br (soluble in PO and PC at high temperature but not at room temperature) could efficiently catalyze the cycloaddition reaction of CO2 and propylene oxide to afford a turnover frequency of 433 h−1. The high catalytic activity is mainly attributed to the efficient cooperation of P-POF-Zn (Lewis acid site) and [CPeDMAPy]Br (nucleophile). Both P-POF-Zn and [CPeDMAPy]Br could be fully recovered after reaction by simple filtration for stable recycling. This work demonstrates the efficiency of the combination of thermal-responsive reagents with solid catalyst for catalyzing chemical reactions via a cooperation activation pathway.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）