PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2017
·Vol. 35
·期 5
·1700377
·
IF 4.474
Yaping Li,Qiaoxi Liu,Jianbo Jin,Wei Ye,Canyu Hu,Shanwei Hu,Zeming Qi,Ran Long,Li Song,Junfa Zhu,Yujie Xiong
The heterogeneous nanocatalyst based on palladium (Pd) is one of the most preferable choices for catalytic hydrogenation reactions as the adsorption and dissociation of hydrogen molecules (H 2 ) are almost spontaneous on Pd surface to form the adsorbed H atoms (H ad ). However, in terms of alkyne semihydrogenation, it remains a grand challenge to optimize both the activity and selectivity of reactions using bare Pd catalysts as the case is largely complicated by the excessive H ad produced from rapid H 2 dissociation and the strong Pd-H binding. In this communication, a well-designed model is developed for seeking a selective semihydrogenation catalyst based on surface lattice engineering. In the proposed model, the ultrathin atomic layer of AuPd shell is grown on the Au nanocubes. The Au nanocubes provide specific facets as substrates for hosting catalytic sites, which can also provide information for further lattice engineering design. While Pd atoms are the active centers for hydrogenation reactions in the nanostructures, alloying Pd atoms with Au in the shells can significantly alter the binding of H ad to metals. As such, the activity and selectivity in catalytic alkyne semihydrogenation can be substantially maneuvered by tailoring the atomic arrangement of Pd and Au on surface. As a proof of concept, the Au@AuPd nanocatalyst with a surface Pd/Au ratio of 1:4 achieves a 98.9% semihydrogenation selectivity with a conversion of 98.2% in the 2-methyl-3-butyn-2-ol (MBY) hydrogenation reaction.
研究领域:
材料科学
·
催化化学
·
纳米技术
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Rufen Wu,Kai Li,Chenyang Shen,Juan Huang,Zeyu Gao,Keru Tang,Yumin Leng,Zhengbo Chen
The effective recognition of antioxidants is considered to have far-reaching significance in medical diagnosis. Here, an efficient visual sensing strategy is developed to identify multiple antioxidants, which takes advantage of the etching of two gold nanomaterials (i.e., Au nanorods (Au NRs) and Au nanobipyramids (Au NBPs)) by the oxidation product (TMB2+) of tetramethylbenzidine (TMB). TMB is oxidized to TMB2+, catalyzed by horseradish peroxidase (HRP), and TMB2+ can etch Au NRs and Au NBPs, resulting in the changes in the wavelength and color of the solution. Various antioxidants react with TMB2+ to varying degrees, resulting in different amounts of remaining TMB2+ and causing different degrees of Au etching, which realized the discrimination and determination of the eight antioxidants with a limit of detection of 100 nM. Importantly, our sensor array also showed excellent practical application capability in human serum samples.
研究领域:
生物医学
·
化学传感
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2014
·
IF 2.354
Tianqi Li,Haihui Zhou,Jiaqi Huang,Junli Yin,Zhongxue Chen,Dan Liu,Ningshuang Zhang,Yafei Kuang
Pd–Au bimetallic nanoparticles were facilely prepared on Ni foil substrate via in-situ self-assembly in reverse microemulsion of water/Triton X-100/n-hexanol/n-hexane. The Pd–Au nanomaterials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). A homogeneous alloy structure of Pd–Au in the bimetallic nanoparticles is indicated by XRD analysis and TEM. The SEM results show that the resultant bimetallic nanoparticles disperse uniformly on Ni foil with a narrow size distribution. The apparent size of bimetallic nanoparticles deposited on Ni depends on the reaction time of self-assembly. The TEM results reveal that the Pd–Au bimetallic nanoparticles consist of smaller homogeneous alloy nanoparticles with an average diameter of 5.1 nm, size of which depends on the size of micro water droplets. The growth mechanism of the Pd–Au nanoparticles in microemulsion was also explored. The electrocatalytic performance of the Pd–Au NPs/Ni electrode was studied by cyclic voltammetric and chronoamperometric measurements. Electrochemical experiments show that the Pd–Au nanoparticles have good catalytic activity and good stability for ethanol oxidation in alkaline media.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Kuan Wang,Zhe Cao,Junlei Wang,Zhen-Hong He,Dan Wang,Rong-Rong Zhang,Weitao Wang,Yang Yang,Zhao-Tie Liu
The development of non-precious metal catalysts in heterogeneous catalytic processes is of great importance to the hydrogenation of quinolines for both theoretical and industrial applications. Herein, an effective non-precious metal catalyst, 58% Fe 4 Ni 6 Cu 5 /MCM-41, was developed to catalyze the hydrogenation of quinolines under the green and mild conditions, which can achieve 97.5% conversion and exceeding 98% selectivity to tetrahydroquinoline in solvent-free at low temperature of 50 °C. Moreover, the acceptable results of the reusability and gram scale-up experiments proved an industrial application potential of the as-prepared catalyst. Meanwhile, in cyclohexane system, 58% Fe 4 Ni 6 Cu 5 /MCM-41 catalyst can further realize a higher activity of the hydrogenation at a lower temperature of 40 °C, achieving 98.2% conversion and 98% selectivity to tetrahydroquinoline. The existence of Fe-Ni and Ni-Cu alloys in Fe 4 Ni 6 Cu 5 /MCM-41 catalyst was demonstrated by TEM, XRD, XPS, H 2 -TPD, and Raman spectroscopy. And, Fe-Ni and Ni-Cu alloys can be well dispersed onto MCM-41 molecular sieves. For Fe 4 Ni 6 Cu 5 /MCM-41 catalyst, quinoline molecules can be adsorbed by Fe 3+ species on the surface of Fe-Ni alloy through the coordination, while hydrogen molecules can be adsorbed and activated by Ni-Cu alloy. Under the synergism of Fe-Ni and Ni-Cu alloys, the highly effective and selective hydrogenation of quinolines was achieved at low temperature and in solvent-free system. The present approach offers a prospective idea for building non-precious metal catalysts to realize the effective hydrogenation of N-heterocyclic compounds under mild conditions.
研究领域:
催化化学
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材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2023
·Vol. 15
·期 6
·e202300217
·
IF 4.5
Shanshan Chai,Denglei Gao,Jing Xia,Yanpeng Yang,Xi Wang
Graphical Alloy catalyst for acetylene hydrogenation: A palladium-silver dilute alloy catalyst (Pd x Ag/Al 2 O 3 ) was fabricated and showed an outstanding performance for acetylene hydrogenation, which contains the Pd 1 Ag single-atom-alloy (SAA) and Pd 2 Ag dimer-alloys (DA) species. Selective hydrogenation of acetylene (C 2 H 2 ) to ethylene (C 2 H 4 ) has been recognized as an important strategic reaction for the removal of trace acetylene from ethylene. Palladium-based alloys are one of the most commonly used catalysts for this reaction but bear a high price and unsatisfactory catalytic performance. Here, we develop a feasible strategy toward the synthesis of a palladium-silver dilute alloy catalyst (Pd x Ag/Al 2 O 3 ), which contains the Pd 1 Ag single-atom-alloy (SAA) and Pd 2 Ag dimer-alloy (DA) species. This catalyst exhibits a high ethylene (C 2 = ) yield of 90.1 % even after 100 hours at 60 °C, which is 11.9 times higher than that of the PdAg/Al 2 O 3 alloy catalyst. Based on in-situ spectroscopic investigations and theoretical calculations, both Pd 1 Ag SAA and Pd 2 Ag DA species in Pd x Ag/Al 2 O 3 are easier to desorb C 2 H 4 compared with PdAg/Al 2 O 3 , and they experience the possible hydrogenation paths with the low energy barriers to yield C 2 = . Furthermore, Pd x Ag/Al 2 O 3 is beneficial to restraining coking due to the endothermic C−H bond cleavage. Thus, these combined merits contribute to the superior catalytic performance for Pd x Ag/Al 2 O 3 .
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
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Huidong Li,Yiyun Zhang,Jifan Zhang,Kefeng Huo,Junqi Gu,Yao Zhou,Yi Liu,Yanli Liu,Xunyong Liu
Too much or too little iodine in the body can affect person's health. Therefore, iodide detection is particularly important. In this work, a novel bimetallic nanoparticle sensor based on colorimetric signal responses was developed for the visual detection of I − . Gold nanoparticles (AuNPs) were prepared by in situ reduction of chloroauric acid using gelatine (Gel) as reducing agent, and further constructed as gold-platinum (Au-Pt) alloy nanoparticle. Au-Pt alloy have unique structure and excellent synergistic effects, which provide higher I − detection sensitivity and stability compared to single-metal nanoparticles. The probe undergoes a redox reaction with I − , which causes the colour to change from buff to rufous, enabling colorimetric detection of I − . The probe is more eye-catching than commonly reported I − detectable colour change based on the aggregation of single metal nanoparticles, and this colour change based on steady-state chemical reactions can remain stable for a long time, which makes it easy to record and detect. The probe showed good linearity over the I − concentration range of 0–1.1 mM with a linear fit coefficient of 0.9943 and a lowest limit of detection (LOD) of 0.29 μM. Moreover, the probe showed very high selectivity for I − and was successfully applied to detection of I − in seawater and tap water. More importantly, the probe remains stable at a temperature of 50 ℃ and a salinity of 12 g/L, broadening its practical application range in a variety of harsh conditions. In summary, the probes have great potential for I − detection and analytical applications.
研究领域:
分析化学
·
纳米技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2022
·
IF 13.599
Jingjing Cai,Huijun Liu,Yulin Luo,Yuqing Xiong,Lizhu Zhang,Sheng Wang,Kang Xiao,Zhao-Qing Liu
Bimetallic sulfides, integrating the merits of individual components, are ideal structures for efficient electrocatalysis. However, for bimetallic sulfides including metal sulfide heterojunctions (MSH) and single-phase bimetallic sulfides (SBS), it is still unclear about which one has better catalytic activity toward reversible oxygen catalysis and its difference on catalytic mechanism. In this work, we demonstrate a bimetallic sulfide electrocatalyst that could transform from metal sulfide heterojunction (CoS/FeS) to single-phase bimetallic sulfide (CoFeS 2 ) through a facile temperature control strategy. The single-phase bimetallic sulfide (CoFeS 2 ) affords high intrinsic activity, fast reaction kinetics and superior durability toward oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Density functional theory (DFT) simulations reveal that the (CoFeS 2 ) has homogeneous electron distribution of the CoFeS 2 structure, improves the central energy level of d band, and optimizes the O* and OOH* intermediate and efficiently reduces the energy barrier of the reaction rate-determining step (RDS). The assembled rechargeable zinc-air battery is more stable than the Pt/C and IrO 2 assemblies due to the excellent electrocatalytic activity and stability of CoFeS 2 /NC, suggesting that it has potential for use in practical applications.
研究领域:
材料科学
·
电化学
·
理论计算
✓ 已验证
DOI
高影响因子
MOLECULES
·
2019
·Vol. 24
·期 13
·2442
·
IF 3.06
Pengfei Zhuang,Peng Zhang,Kuo Li,Beena Kumari,Dan Li,Xifan Mei
Metal nanomaterials have been reported as effective absorbents for the removal of pollutants in the water system, but the release of ions from these nanomaterials brings another concern. Herein, silver nanoclusters (AgNCs) were encapsulated in porous metal-organic frameworks of ZIF-8 (MOF-AgNCs). Compared to AgNCs, the release of Ag+significantly decreases from MOF-AgNCs, indicating that the product presents a lower threat to the environment. The MOF-AgNCs were employed for the rapid removal of heavy metals, such as Pb2+and Mn2+, from water. The mechanism and removal efficiencies were investigated.Keywords:nanoclusters;metal-organic frameworks;heavy metal ions
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Haoyu Zhang,Baoguo Zhang,Bing Ai,Kefeng Pan,Weimin Zhang,Lipeng Zhang,Zhongning Shi
The high chemical activity of metallic Li hinders its efficient electrochemical extraction at low temperatures, necessitating the use of energy- and cost-intensive methods such as vacuum thermal reduction or electrodeposition from ionic-liquid and molten-salt electrolytes. Herein, we report the direct room-temperature electrowinning of metallic Li from a simple low-cost electrolyte, namely a solution of LiCl in dimethylacetamide (DMAc), determine the optimal concentration of LiCl, and examine the redox processes in the optimized system. Potentiostatic deposition on high-purity Al is shown to induce solid-state cathode alloying and thus produce a uniform, flat, and dense coating of a LiAl master alloy comprising spherical clusters formed by LiAl alloy nanosheets. Finally, the direct smelting of electrodeposited films is proposed as a method of rapidly realizing the “thin film” to “bulk” transformation of electrodeposited materials to stabilize metallic Li and form bulk Li-based alloys. Thus, this study provides a basis for the continuous, low-cost, sustainable, and fast electrochemical production of bulk active metals or their alloys.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2014
·
IF 5.211
Li-Li He,Jie-Ning Zheng,Pei Song,Shu-Xian Zhong,Ai-Jun Wang,Zhaojiang Chen,Jiu-Ju Feng
In this work, a facile one-pot wet-chemical method is developed for preparation of bimetallic platinum–gold (Pt–Au) alloyed string-bead nanochain networks, using allantoin as a structure-directing agent, without any template, surfactant , or seed. The characterization experiments are mainly performed by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) spectroscopy. The as-prepared Pt–Au nanocrystals show enhanced electrocatalytic performance toward oxygen reduction reaction (ORR) mainly predominated by a four-electron pathway, and display improved catalytic activity and high stability for methanol oxidation reaction (MOR) over commercial Pt black and Pt–Ru black.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ChemSusChem
·
2013
·Vol. 6
·期 8
·1545-1555
·
IF 7.475
Jinzhu Chen,Shengpei Wang,Jing Huang,Limin Chen,Longlong Ma,Xing Huang
Graphical Acid/Metal Balance : Bifunctional catalysts containing ruthenium and polyoxometalates as active species with a metal-organic framework as support and encapsulation matrix, respectively, are synthesized. Excellent yields in sorbitol are obtained in the conversion of cellobiose and ball-milled cellulose. The evaluation of the balance between the hydrogenation and hydrolysis functions of these bifucntional catalysts reveals that by carefully balancing the ratio of acid site density and the number of metal surface atoms a maximum conversion can be achieved. Cellulose and cellobiose were selectively converted into sorbitol over water-tolerant phosphotungstic acid (PTA)/metal– organic-framework-hybrid-supported ruthenium catalysts, Ru-PTA/MIL-100(Cr), under aqueous hydrogenation conditions. The goal was to investigate the relationship between the acid/metal balance of bifunctional catalysts Ru-PTA/MIL-100(Cr) and their performance in the catalytic conversion of cellulose and cellobiose into sugar alcohols. The control of the amount and strength of acid sites in the supported PTA/MIL-100(Cr) was achieved through the effective control of encapsulated-PTA loading in MIL-100(Cr). This design and preparation method led to an appropriately balanced Ru-PTA/MIL-100(Cr) in terms of Ru dispersion and hydrogenation capacity on the one hand, and acid site density of PTA/MIL-100(Cr) (responsible for acid-catalyzed hydrolysis) on the other hand. The ratio of acid site density to the number of Ru surface atoms ( n A / n Ru ) of Ru-PTA/MIL-100(Cr) was used to monitor the balance between hydrogenation and hydrolysis functions; the optimum balance between the two catalytic functions, that is, 8.84< n A / n Ru <12.90, achieves maximum conversion of cellulose and cellobiose into hexitols. Under the applied reaction conditions, optimal results (63.2 % yield in hexitols with a selectivity for sorbitol of 57.9 % at complete conversion of cellulose, and 97.1 % yield in hexitols with a selectivity for sorbitol of 95.1 % at complete conversion of cellobiose) were obtained using a Ru-PTA/MIL-100(Cr) catalyst with loadings of 3.2 wt % for Ru and 16.7 wt % for PTA. This research thus opens new perspectives for the rational design of acid/metal bifunctional catalysts for biomass conversion.
研究领域:
催化化学
·
生物质转化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROANALYSIS
·
2016
·Vol. 29
·期 2
·602-608
·
IF 2.471
Zhiming Jiang,Qin Liu,Yuran Tang,Mingxiao Zhang
Pt−Au nanoclusters decorated on the surface of reduced graphene oxide (rGO/Pt−Au) was facilely prepared by one-pot electrochemical reduction. The morphology and composition of rGO/Pt−Au composites had been characterized by scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectrometry (EDX), fourier transform-infrared spectroscopy (FT-IR) and electrochemical methods. Ofloxacin is a member of synthetic quinolones which has been widely used for the treatment of common diseases in humans and animals. The performance of the rGO/Pt−Au nanocomposite toward the oxidation of ofloxacin was compared with the other similar nanostructures like rGO/Pt and rGO/Au. In the optimized conditions, two linear calibration curves were obtained, from 0.08 to 10 μM and 10 to 100 μM ofloxacin. A detection limit of 0.05 μM ofloxacin was observed at pH 5.7 for the GCE/rGO/Pt−Au. The proposed sensor was successfully applied to determine ofloxacin in tablets and human urine samples and the results were satisfactory.
研究领域:
分析化学
·
材料科学
·
环境科学
✓ 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）