GREEN CHEMISTRY
·
2022
·Vol. 24
·期 22
·8840-8852
·
IF 11.034
Zongyang Liu,Yuan Tan,Jie Li,Xiuli Li,Yan Xiao,Juan Su,Xingkun Chen,Botao Qiao,Yunjie Ding
Aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is a promising alternative route to produce renewable biodegradable plastics, which has stimulated intense interest in recent years. Supported gold catalysts have shown great potential for this reaction, but the selectivity and stability need to be improved. In addition, the requirement for base additives makes the process less effective and sustainable. Herein, highly active and selective Au–Ag bimetallic nanoclusters supported on MgAl-hydrotalcite (HT) were developed for HMF oxidation to FDCA under base-free reaction conditions using molecular oxygen as the oxidant. The presence of small amounts of Ag (0.034–0.065 wt%) in Au25 clusters greatly enhanced the catalytic reaction rates and selectivity for HMF tandem oxidative steps, leading to both high conversion of HMF (>97%) and high yield of FDCA (>95%). Besides, the catalyst stability was also enhanced by the addition of Ag. The characterization results suggested that the substitution of Ag atoms modified the electronic structure of Au while likely maintaining the primary geometry. Thus, a significant synergistic effect could be observed over trace Ag modified Au–Ag bimetallic nanoclusters. The present work provides new insight into the alloying effect, and helps understand highly efficient Au-based catalysts for aerobic oxidation of biomass derived molecules under base-free conditions.
研究领域:
催化化学
·
可再生资源化学
✓ 已验证
DOI
高影响因子
Advanced Sustainable Systems
·
2023
·Vol. 8
·期 2
·2300331
·
IF 7.1
Cailing Yang,Wenxu Zhang,Rongnian Xu,Huaiwu Peng,Zhenshi Zhang,Xiaomei Liu,Li Li,Tingli Li,Jing Li,Pengbo Liu,Xinlu Jin,Yuanyuan Ma,Ziqiang Lei
Modified MIL-101(Al)-NH 2 (MIL-101(Al)-NH 2 -net) is used as a crosslinking agent and acrylic acid (AA) as a monomer, the MIL-101(Al)-NH 2 -net grafted polyacrylic acid (MIL-101(Al)-NH 2 -net-g-PAA (MAP)) composite water-absorbent material is synthesized using the free radical polymerization method to study the application of composite absorbent materials in water collection. The structure and morphology of the composite water-absorbent material are characterized using Fourier transform infrared spectrometry (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), Brunauer Emmett Teller (BET), and thermogravimetric analysis (TG), and the contents of ammonium persulfate (APS), MIL-101(Al)-NH 2 -net, and neutralization degree of AA are optimized. Under optimal conditions, the water absorption ratios of the composite materials in distilled water, tap water, and 0.9% NaCl solution are 744, 169.5, and 85.5 g g −1 . In addition, the properties of collecting water vapor are investigated. At 25 °C, 50% Relative Humidity (RH), 70% RH, and 90% RH, the MAP water vapor adsorption capacity is 0.0312, 0.5760, and 1.6856 g g −1 , respectively. The water vapor adsorption of MIL-101(Al)-NH 2 and MIL-101(Al)-NH 2 self-polymerization products are 0.025 and 0.1278 g g −1 , respectively. The result showed that autopolymerization can improve the water vapor adsorption performance.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Linjia Li,Yiran Zhang,Jiaqi Feng,Shu Zhao,Ke Li,Zhen Huang,He Lin
Integrated carbon capture and utilization (ICCU), based on dual-function materials (DFMs), is an emerging technology for carbon dioxide (CO2) emission control. DFMs composed of Ni–Ca–Al systems are favored owing to their affordability. However, their performance needs to be further improved. In this study, Ni/AlCaOx DFMs are prepared by one pot-impregnation method, reaching an adsorbing capacity of 1796 μmol CO2/gDFM and a production of 1790 μmol CH4/gDFM after ten cycles at 450 °C. The Ni–Ca–Al synergistic effect was investigated to understand the good performance of DFMs: during H2 pretreatment, Ca can weaken the strong interaction of Al–Ni and promote the reduction of NiO by facilitating Ni to gain electrons from H2, where Al may act as an intermediate carrier for electron transfer. In the carbonation process, Al modulates the synergistic interaction between Ca and Ni by regulating the spacing and distribution of catalytic and adsorption sites to improve the Ni/AlCaOx cycling performance. Besides, oxygen vacancies can also enhance the DFMs’ carbon capture performance. During the methanation process, Ni reduces the decomposition temperature of the carbonate formed at strongly basic sites, favoring the methanation reaction.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Hanqin Liang,Huilu Guo,Jinwei Yin,Kaihui Zuo,Yongfeng Xia,Dongxu Yao,Jian Zhang,Yuping Zeng,Shiwei Wang
Transparent AlON ceramics were bonded with Lu-Al-Si-O-N oxynitride glass interlayer at 1450 °C in nitrogen atmosphere in this investigation. The Lu-Al-Si-O-N oxynitride glass showed good wettability on the AlON substrate and had strong interface adhesion with each other. The joining process had no detrimental effect on the in-line transmittance of transparent AlON ceramics but caused slight decrease of flexural strength due to the partial decomposition. The bonding strength of AlON/AlON joint was 142.7 ± 6.3 MPa at room temperature and 110.1 ± 9.6 MPa at 1200 °C in situ, which were comparable with those of the parent AlON ceramics. Some Lu 2 Si 2 O 7 grains crystallized out from the glass interlayer after joining.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2024
·
IF 4
Mengjiao Yu,Xiong-Fei Zhang,Siting Yang,Yunhua Bai,Zhongguo Wang,Jianfeng Yao
Developing functional catalysts with both Lewis and Brønsted acid sites is an essential task for achieving the direct conversion of glucose to 5-hydroxymethylfurfural (5-HMF), a process that is crucial for the sustainable production of renewable fuels and chemicals. In this work, a mixed-linker strategy is proposed to prepare defective MIL-53(Al)-NH 2 by introducing trifluoroacetic acid into the MIL-53(Al)-NH 2 synthesis process. The creation of defects facilitates the exposure and accessibility of Al 3+ centers, as well as changes the coordination environment within the MIL-53(Al)-NH 2 skeleton. Both the number of Lewis and Brønsted acid sites are boosted, which is beneficial for glucose activation and 5-HMF generation. Through optimizing the reaction conditions, a glucose conversion of 98.3 % with a 5-HMF yield of 59.3 % was achieved by using defective 6d-MIL-53(Al)-NH 2 in a biphasic tetrahydrofuran/H 2 O NaCl system. Moreover, the 6d-MIL-53(Al)-NH 2 catalyst showed excellent recyclability and reusability, with its catalytic efficiency maintained almost unchanged for consecutive 10 cycles. The catalytic mechanism was elucidated and the acidity of the Lewis and Brønsted acid was modulated by defect engineering to achieve exceptional performance.
研究领域:
化学工程
·
催化科学
·
可再生资源
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Pu Zhao,Zhengwei Li,Zhiwu Xu,Xuesong Liu,Jiuchun Yan
How to obtain a high-strength and corrosion resistance of Al/Sn/Al joint has been a longstanding goal for electronics industry. In this work, 6063Al was joined in the air by ultrasonic-assisted liquid phase diffusion bonding using a Sn filler metal . It was performed by applying an uninterrupted ultrasonic vibration at a heating temperature of 360 ℃, final obtaining a 6063Al joint without enriched-Sn. Under the action of ultrasonic vibrating, the breaking of oxide film , the diffusing of Sn, and dissolving of Al alloy occurred in sequence. It resulted in a transition of bonding interface from Sn/Al to an α-Al/α-Al bonding interface embedded a few Mg 2 Sn partials, after depleting Sn by grain boundary diffusion . The joints possessed a high strength coefficient of 86.7% of 6063Al base metal and 161.8% of soldering joint. The joint had a better corrosion resistance that the tensile strength only reduced 35.3% after a corroding of 72 h in 3.5 wt% NaCl solution in comparison with the soldering joints. Finally, the evolution of the interface structure and mechanism of improving corrosion resistance were discussed in detail. It is a promising technology for manufacturing high-reliable Al/Sn heterogeneous joints.
研究领域:
材料科学
·
焊接技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zhiyu Ma,Weijia Guo,Zhenxing Yue
TiO 2 -added Ba 4 (Sm 0.65 Nd 0.35 ) 9.33 Ti 17.75 Al 0.33 O 54 (BSNTA) ceramics were fabricated with a solid-state reaction method. Slight TiO 2 addition increased the dielectric constant ( ε r ) of BSNTA ceramics and brought about a near-zero temperature coefficient of resonant frequency ( τ f ). Sintering in oxygen increased the density of TiO 2 -added BSNTA ceramics and surprisingly concurrently improved the ε r and Q × f value. Thermally stimulated depolarization current (TSDC) measurements indicated that TiO 2 addition introduced oxygen vacancies ( V O .. ) and Ti Ti ' − V O .. defect dipoles and that an oxygen-sufficient sintering atmosphere decreased the concentration of these defects and thus increased Q × f values. From the viewpoint of defect behaviors, this observation offered original insight into the mechanism by which the sintering atmosphere had impacts on the Q × f value of titanate ceramics. Satisfying dielectric properties ( ε r = 79.5, Q × f = 14,840 GHz, τ f = 0 ppm/°C) were attained in oxygen-sintered BSNTA-0.6%TiO 2 ceramics that might be suitable for the manufacture of miniature microwave devices such as filters and antennas.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 7
·1113
·
IF 2.467
Zhe Wang,Xiaoping Shen,Temeng Qian,Kang Xu,Qingfeng Sun,Chunde Jin
The hydrophilicity and flammability of fiberboards have limited their real-life applications. In this study, a facile strategy for preparing the multifunctional coatings with superhydrophobicity and flame retardancy on medium density fiberboards (MDFs) has been investigated. The superhydrophobic and flame-retardant coating on the MDF surface was obtained by depositing polydimethylsiloxane (PDMS) and 1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane (FDTS)-modified Mg/Al layered double hydroxide (LDH) particles step by step. The as-prepared coating exhibited superhydrophobic properties with a water contact angle (WCA) of ~155° and good self-cleaning properties. Furthermore, the limiting oxygen index (LOI) value of the superhydrophobic MDFs increased by 60.4% as compared to that of the pristine MDFs, showing improved flame retardancy. The peak heat release rate (PHRR) and total heat release (THR) of MDFs decreased after coating with PDMS@FDTS-Mg/Al LDH, suggesting that the superhydrophobic coating decreased the fire growth speed and risk of fire hazard of MDFs. This coating with multiple functions opens a new avenue for the protection and functionalization of MDFs.Keywords:medium density fiberboard;Mg/Al LDH;FDTS;superhydrophobicity;flame retardancy
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2016
·Vol. 6
·期 14
·5656-5667
·
IF 5.287
Fufeng Cai,Guomin Xiao
In this work, a series of Cu–Co–Al catalysts with different Ce loadings were applied to the hydrogenolysis of glycerol to 1,2-propanediol in a fixed-bed flow reactor. The physicochemical properties of the synthesized catalysts were analyzed using BET, N2O chemisorption, SEM, TEM, XRD, H2-TPR, NH3-TPD and XPS techniques. Systematic characterization demonstrated that the incorporation of Ce into the Cu–Co–Al catalyst could effectively restrain the aggregation of active metal species as well as the growth of metallic particles during calcination and reduction, which resulted in the formation of highly dispersed active metals. Large amounts and superior strength of acid sites were present in the Ce-promoted Cu–Co–Al catalysts, as confirmed by NH3-TPD analysis. The reducible nature of the Cu–Co–Al catalyst greatly increased after the addition of Ce. The higher concentration of acid sites, excellent reducibility and highly dispersed active metals were responsible for the superior catalytic activity of the 8Ce/Cu–Co–Al catalyst and it attained 91.6% glycerol conversion and 92.4% 1,2-propanediol selectivity. In addition, the effects of different process parameters such as the solvent, reaction temperature, operating pressure, catalyst loading, glycerol concentration and liquid flow rate on glycerol hydrogenolysis together with the catalyst stability were studied in detail, showing that the Ce-promoted Cu–Co–Al catalyst had high efficiency and stability for glycerol hydrogenolysis.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 42
·21029-21038
·
IF 9.931
Liang Zhang,Jing Wang,Xinyi Ren,Wentao Zhang,Tianshu Zhang,Xinnan Liu,Ting Du,Tao Li,Jianlong Wang
The excessive accumulation of toxic copper species makes it imperative to develop smart dual-functional materials for the simultaneous removal and detection of Cu(II) in drinking water. In this work, novel core–shell NH2-MIL-101(Al)@ZIF-8 nanoflowers were successfully fabricated via an internal extended growth mode under the regulation of polyvinylpyrrolidone (PVP) to achieve this goal. Benefiting from the specific affinity of imidazole nitrogen in ZIF-8 toward Cu(II), the resultant NH2-MIL-101(Al)@ZIF-8 shows high adsorption capacity (526.74 mg g−1). Moreover, the fluorescence of NH2-MIL-101(Al) shows a Cu(II)-dependent change, causing this composite to possess superior selective/sensitive detection with a broad linear range (1.5–625 μM) and a low detection limit (0.17 μM) for Cu(II). Specifically, the hybrid MOF@MOF structure provides greater sensitivity as compared to the individual constituent (pristine NH2-MIL-101(Al)) and the mixed state, which is ascribed to the rational optimization of the smart adsorbent based on the following two aspects. (i) The synergistic effect of the core–shell nanostructure improves the preconcentration ability at the interface between single MOFs. (ii) The existence of the three-dimensional hierarchical nanoflower architecture (structure optimization) accelerates the mass transport and sculpts the final composite with enhanced adsorption and detection ability. These indicate that the smart NH2-MIL-101(Al)@ZIF-8 nanoflower could be an excellent candidate for the synchronous remediation and selective detection of Cu(II) in aqueous systems, which could be potentially useful in wastewater treatment and water quality monitoring.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
DOI
高影响因子
ANALYST
·
2011
·Vol. 137
·期 1
·133-139
·
IF 3.913
Cheng-Xiong Yang,Shan-Shan Liu,He-Fang Wang,Shan-Wei Wang,Xiu-Ping Yan
Metal–organic framework MIL-53(Al) was explored as the stationary phase for high-performance liquid chromatographic separation of position isomers using a binary and/or polar mobile phase. Baseline separations of xylene, dichlorobenzene, chlorotoluene and nitrophenol isomers were achieved on the slurry-packed MIL-53(Al) column with high resolution and good precision. The effects of mobile phase composition, injected sample mass and temperature were investigated. The separation of xylene, dichlorobenzene, chlorotoluene and nitrophenol isomers on MIL-53(Al) were controlled by entropy change.
研究领域:
化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Mian Yang,Kaihua Chen,Shenghui Guo,Ming Hou,Jiyun Gao,Junwen Zhou,Shuhao Shi,Li Yang
In this paper, the self-propagating reaction of the Ti–SiC–C system for synthesising Ti 3 SiC 2 -based diamond composites is ignited by the combustion of Ni–Al alloy powders in a microwave field. The heating curves of Ni–Al-assisted microwave sintering show that the self-propagating reaction could be successfully ignited after heating samples to 685.2 °C in a microwave field for 456 s. This finding indicates that ignition could occur at temperatures below the diamond graphitisation temperature (727 °C). X-ray diffraction analysis indicates that the sintered samples primarily comprise Ti 3 SiC 2 , TiC, Ti 5 Si 3 and C. Scanning electron microscopy coupled with energy dispersive spectroscopy observations demonstrates that the diamond grains are tightly bonded with the surrounding matrix and are intact. The best wear ratio of 302.26 was obtained for the Ti 3 SiC 2 -bonded diamond composite when the diamond grain size was 140/170 mesh and the molar ratio of Ti, SiC and C was 3:1.1:0.9.
研究领域:
材料科学
·
复合材料工程
✓ 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）