Polymers
·
2022
·Vol. 14
·期 17
·3630
·
IF 4.967
Guangxu Bo,Xiaoling Xu,Xiaoke Tian,Jinyong Yan,Xingjian Su,Yunjun Yan
Rigid polyurethane foams (RPUFs) as building insulation materials quickly burn and release a lot of heat, smoke, and carbon monoxide, and cause human safety risk and severe environmental pollution. To mitigate these disadvantages, MOF/MWCNTs were fabricated via mixing Cu ions’ partly substituted framework of ZIF-67 and MWCNTs, and further calcinated MOF/MWCNTs (C-MOF/MWCTs) was newly generated by calcinating MOF/MWCNTs in air. Then, MOF/MWCNTs and C-MOF/MWCNTs were respectively employed together with a phosphorus–nitrogen-containing reactive flame retardant (TBPBP) to prepare renewable bio-based rigid polyurethane foam, including RPUF-T/MOF/MWCNTs 2 and RPUF-T/C-MOF/MWCNTs 2. The characterization results showed that RPUF-T/C-MOF/MWCNTs 2 had better performance than RPUF-T/MOF/MWCNTs 2 and neat RPUF. Compared to neat RPUF, the compressive strength, limiting oxygen index value, and the mass char residue in cone calorimetry test of RPUF-T/C-MOF/MWCNTs 2, respectively, were increased by 105.93%, 46.35%, and 347.32%; meanwhile, the total heat release rate, total smoke production, total carbon monoxide product, and total carbon dioxide product were reduced by 47.97%, 50.46%, 41.38%, 43.37%, respectively. This study provides a referable method for preparing RPUFs with good physical properties, fire, and smoke safety, which is favorable for human safety and environmental protection as new building insulation materials.Keywords:building insulation materials;C-MOF/MWCNTs;phosphorus–nitrogen-containing reactive flame retardant (TBPBP);bio-based rigid polyurethane foam;fire and smoke safety;environmental protection
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PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhenfei Liu,Dingding Ye,Xun Zhu,Shaolong Wang,Yanan Zou,Linghan Lan,Rong Chen,Yang Yang,Qiang Liao
Non-precious metal materials are considered as the most promising catalysts for oxygen reduction reaction (ORR) due to their high catalytic activity, low cost, superior stability as well as good electrocatalytic selectivity. Here, in situ encapsulation of Co nanoparticles into N-doped porous carbon (Co@NPC) nanocages interconnected by carbonized multi-walled carbon nanotubes (C-MWCNTs) are prepared through direct carbonization of the MWCNTs-based ZIF-67 precursor. The obtained hybrid material (denoted as Co@NPC/C-MWCNTs) displays an excellent ORR performance with a half-wave potential of 0.79 V, effective four-electron transfer and superior formate-tolerance ability. The superior ORR activity of the Co@NPC/C-MWCNTs hybrids is mainly ascribed to the abundant catalytic active sites contributed by the Co@NPC nanocages, the high electrical conductivity and large specific surface area rooting in C-MWCNTs, and synergetic effects between Co@NPC nanocages and C-MWCNTs. The membraneless flexible direct formate fuel cell (DFFC) using Co@NPC/C-MWCNTs as the cathode catalyst delivers a peak power density of 4.32 mW cm −2 stably. Notably, the performance of the flexible DFFC can still maintain 90.9% of its initial value after repeated bending for 1000 times. Moreover, two flexible DFFCs connected in series mode can easily power some low-power electronics. The report not only opens a new door to design high-performance non-precious metal ORR catalysts for DFFCs, but also greatly boosts the development of flexible energy conversion and storage devices.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhikun Wang,Zhihua Zhao,Chen Chen,Guixin Jin,Xiaoqing Shen,Zhigang Shao,Lan Wu
Environmental safety monitoring has significantly benefited from the incorporation of gas sensors. Given the pernicious effects of ammonia and acetic acid gases on the environment and human health, it is imperative to develop a room temperature dual-functional gas sensor capable of simultaneously detecting both these gases. In this research endeavor, acid-functionalized multi-walled carbon nanotubes (f-MWCNTs) were integrated with Bi 2 S 3 through a hydrothermal approach, leading to the fabrication of a Bi 2 S 3 /f-MWCNTs-2 nanocomposite-based chemoresistive gas sensor. The results demonstrate that the Bi 2 S 3 /f-MWCNTs-2 sensor exhibits a response value of 52.7 % towards 100 ppm NH 3 at room temperature (25℃), displaying a declining resistance curve upon exposure to the target gas. Similarly, for 100 ppm CH 3 COOH under ambient conditions (25℃), the sensor records a response value of 72.55 %, accompanied by a rising resistance curve when in contact with CH 3 COOH gas. The distinctive feature of this dual-functional sensor lies in its ability to detect opposing transient response curves for the two gases, which is crucial for distinguishing between different gases. Furthermore, the sensor boasts swift response recovery, excellent repeatability, and robust stability. This study underscores the promising potential of the Bi 2 S 3 /f-MWCNTs-2 nanocomposite sensor in applications such as environmental monitoring.
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高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Shumei Zhao,Yingqing Zhan,Xinyi Wan,Shuangjiang He,Xulin Yang,Jiaxin Hu,Guiyuan Zhang
It is a big challenge to design advanced adsorbents that have high adsorption capacity and excellent selectivity to efficiently remove organic dyes from complex environmental systems. Herein, by utilizing the adhesion property of polydopamine (PDA) and its crosslinking reaction with polyethyleneimine (PEI), a novel core/shell magnetic MWCNTs/Fe 3 O 4 @(PDA + PEI) nano-hybrid that carries superior adsorption performance of dyes was constructed through facile polydopamine tailored graft polymerization. In such hierarchical structure, the inner shell of Fe 3 O 4 nanoparticles and outer shell of (PDA + PEI) contributed to the abundant active adsorption sites, large specific surface area (126 m 2 /g) and high saturation magnetization value (10.91 emu/g). As a result, the prepared adsorbent exhibited highly selective adsorption performance toward multiple anionic dyes, including MB , CR, and MO with maximum adsorption capacity of 1449, 1006, and 935 mg/g at 298.15 K, respectively. It was found that the main adsorption mechanism was attributed to the hydrogen bonding and electrostatic interaction. The kinetics data fitted well with the pseudo-second-order model, and both the Langmuir and Freundlich isotherm models presented well fit to the isotherm data. The investigation of thermodynamic study indicated that the adsorption of anionic dyes onto core/shell magnetic MWCNTs/Fe 3 O 4 @(PDA + PEI) nano-hybrid was spontaneous and endothermic. More importantly, the adsorbent presented excellent regeneration property after multiple adsorption-desorption cycles and prominent stability in harsh environments, especially in the alkaline condition. Therefore, these results revealed the promising applications of hierarchical MWCNTs/Fe 3 O 4 @(PDA + PEI) nano-hybrid in water remediation.
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高影响因子
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
·
2024
·
IF 5.6
Luheng Wang,Maoyuan Nan,Xisi Long
To realize the simultaneous measurement of gap and gas concentration between narrow curved surfaces, in this article, a flexible spiral sensing element based on $\alpha $ -Fe2O3-doped multiwalled carbon nanotubes (MWCNTs) (mass ratio is 100) coated with polytetrafluoroethylene (PTFE) is prepared by spraying and spin coating technology using polyimide (PI) film as the substrate. The spiral structure has eddy current effect under ac excitation, which is sensitive to the change in the gap between the sensing element and metal target. Meanwhile, the $\alpha $ -Fe2O3-doped MWCNTs can respond to gas. The experimental results indicate that the gas response values of impedance amplitude, impedance angle, and resistance are 0.509%, 0.216%, and 1.376% at ethanol vapor concentration of 5000 ppm when the curvature radius is 50 mm with a gap of 0.5 mm, respectively. The absolute/relative sensitivities of impedance amplitude and impedance angle to the gap are 175 $711.54~\pm ~1424.85~\Omega \cdot \text { mm}^{-1}$ /11.347% $\pm ~0.095{\%}\cdot \text { mm}^{-1}$ and $2.614^{\circ }~\pm ~0.015^{\circ }\cdot \text { mm}^{-1}$ /5.307% $\pm ~0.033{\%}\cdot \text { mm}^{-1}$ in the gap range of 0–0.5 mm, respectively. In addition, according to impedance complex plane diagram of the sensing element, a signal processing method based on R–X is proposed, and the ability of flexible spiral sensing element to simultaneously measure the gap and gas concentration between narrow curved surfaces is preliminarily verified.
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高影响因子
RSC Advances
·
2016
·Vol. 6
·期 50
·44865-44872
·
IF 3.289
Yazhen Niu,Junlin He,Yuliang Li,Yilin Zhao,Chunyong Xia,Guolin Yuan,Lei Zhang,Yuchan Zhang,Chao Yu
Sialylated glycans are crucial molecular targets for cancer diagnosis and clinical research. α2,3-Sialylated glycans and α2,6-sialylated glycans are the predominant sialic acids found in nature. Different expression of the quantity of glycans can result in development of different disease. However, there are no ideal methods for discriminating α2,3-sialylated glycans and α2,6-sialylated glycans. In this work, a multi-purpose biosensor is fabricated for sensitive detection of α2,3-sialylated glycans and α2,6-sialylated glycans. To improve the sensitivity of the biosensor, p-MWCNTs were integrated with PAMAM, as PAMAM has highly branched and abundant amino groups, providing a large available surface area for linking with other substances. To achieve distinguishable recognition, Maackia amurensis lectin (MAL) and Sambucus nigra agglutinin (SNA) were included. To facilitate the lectin fixation, PDITC, a kind of green homobifunctional cross-linker, was selected. Under optimized detection conditions, the linear range of detection for α2,3-sialylated glycans is 10 fg mL−1 to 50 ng mL−1 with a lower detection limit of 3 fg mL−1, and the linear range of detection for α2,6-sialylated glycans is 10 fg mL−1 to 50 ng mL−1 with a detection limit of 3 fg mL−1. This work not only provides a method for distinguishing detection of α2,3-sialylated glycans and α2,6-sialylated glycans, but also provides a reference for future clinical testing.
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高影响因子
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