Small
·
2023
·
IF 13.3
Zhiming Deng,Peizhu Jiang,Zhenguo Wang,Li Xu,Zhong-Zhen Yu,Hao-Bin Zhang
Processing transition metal carbides/nitrides (MXenes) inks into large-area functional coatings expects promising potential for electromagnetic interference (EMI) shielding and infrared stealth. However, the coating performances, especially for scalable fabrication techniques, are greatly constrained by the flake size and stacking manner of MXene. Herein, the large-area production of highly densified and oriented MXene coatings is demonstrated by engineering interfacial interactions of small MXene flakes with catecholamine molecules. The catecholamine molecules can micro-crosslink MXene nanosheets, significantly improving the ink's rheological properties. It favors the shear-induced sheet arrangement and inhibition of structural defects in the blade coating process, making it possible to achieve high orientation and densification of MXene assembly by either large-area coating or patterned printing. Interestingly, the MXene/catecholamine coating exhibits high conductivity of up to 12 247 S cm −1 and ultrahigh specific EMI shielding effectiveness of 2.0 ×10 5 dB cm 2 g −1 , obviously superior to most of the reported MXene materials. Furthermore, the regularly assembled structure also endows the MXene coatings with low infrared emissivities for infrared stealth applications. Therefore, MXene/catecholamine coatings with ultraefficient EMI shielding and low infrared emissivity prove the feasibility of applications in aerospace, military, and wearable devices.
研究领域:
材料科学
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电磁干扰
·
红外技术
·
纳米技术
·
航空航天工程
·
军事应用
·
可穿戴设备
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2022
·
IF 7.34
Zongying Zhang,Qinze Liu,Tingting Gao,Congde Qiao,Jinshui Yao,Changbin Zhang
Alkaline lignin, a by-product of the paper-pulping process, can undergo phenolation by pyrogallol in the presence of acetone and sulfuric acid to prepare phenolated-alkaline-lignin (PAL). PAL can be further reacted with tetraethylenepentamine (TEPA) to prepare lignin-based catecholamine (PAL-TEPA), which exhibits excellent ability to remove hazardous Cr (VI) from simulated wastewater. In this study, PAL and PAL-TEPA were systematically investigated by SEM, FT-IR, 1 H NMR, TGA, and XPS. The conditions for the preparation of PAL and the various variables affecting the adsorption behavior of PAL-TEPA were optimized sequentially. The adsorption process followed the pseudo-second-order model and fitted to the Langmuir isotherm equation. The maximum adsorption amount reached 600 mg g −1 ( R = 75 %) under optimized conditions (pH = 2.0, C 0 = 200 mg L −1 , V = 100 mL, T = 30 °C, dos. = 25 mg, t = 24 h). Toxic Cr (VI) ions were successfully converted to harmless Cr (III) ions and removed by PAL-TEPA adsorbent. This approach opens new avenues for the utilization of lignin and new kinds of adsorbent for Cr (VI) removal.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Yuling Ren,Pengfei Qi,Yinhua Wan,Chulong Chen,Xiangrong Chen,Shichao Feng,Jianquan Luo
A nanofiltration (NF) membrane with high salt permeation and high retention of small organics is appealing for the treatment of high-salinity organic wastewater. However, the conventional negatively charged NF membranes commonly show high retention of divalent anions (e.g., SO42–), and the reported positively charged NF membranes normally suffer super low selectivity for small organics/Na2SO4 and high fouling potential. In this work, we propose a novel “etching–swelling–planting” strategy assisted by interfacial polymerization and mussel-inspired catecholamine chemistry to prepare a mix-charged NF membrane. By X-ray photoelectron spectroscopy depth profiling and pore size distribution analysis, it was found that such a strategy could not only deepen the positive charge distribution but also narrow the pore size. Molecular dynamics confirm that the planted polyethyleneimine chains play an important role to relay SO42– ions to facilitate their transport across the membrane, thus reversing the retention of Na2SO4 and glucose (43 vs 71%). Meanwhile, due to the high surface hydrophilicity and smoothness as well as the preservation of abundant negatively charged groups (−OH and −COOH) inside the separation layer, the obtained membrane exhibited excellent antifouling performance, even for the coking wastewater. This study advances the importance of vertical charge distribution of NF membranes in separation selectivity and antifouling performance.
研究领域:
膜科学
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水处理
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环境工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 18
·48640
·
IF 2.188
Song Gao,Gang Wei,Qiang Liu,Qinze Liu,Tingting Gao,Jinshui Yao
Lignosulfonate-based polycatecholamine (PCEA-LS) was synthesized by a two-stage approach involving Mannich and catechol–amine reactions, and it was directly used to adsorb Congo red (CR) from the pH-unadjusted aqueous solution. PCEA-LS was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). Various factors affecting on removal of CR by PCEA-LS were investigated in depth, including contact time, adsorbent dosage, and initial concentration of CR and adsorption temperature. The adsorption kinetics, isotherm, and thermodynamics of PCEA-LS for CR were explored in detail, and then its adsorption mechanism was systematically elucidated. Results indicated that the removal process of CR followed the pseudo-second-order kinetic model, and the isotherm data fitted the Langmuir model well. The maximum adsorption capacity reached 972.6 mg g −1 at 30°C in the pH-unadjusted (pH = 6.25) solution possibly due to the hydrogen bond, π–π stacking, and electrostatic interaction between PCEA-LS and CR. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48640.
研究领域:
环境科学
·
材料科学
·
化学工程
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产品关联
DOI
高影响因子