资源类型

期刊论文 292

会议视频 3

年份

2023 35

2022 36

2021 29

2020 27

2019 17

2018 20

2017 13

2016 12

2015 17

2014 11

2013 13

2012 9

2011 7

2010 5

2009 8

2008 5

2007 11

2006 1

2005 2

2004 2

展开 ︾

关键词

重金属 3

二氧化碳 2

固体氧化物燃料电池 2

带传动 2

显微硬度 2

有色金属工业 2

重金属废水 2

金属带 2

2035 1

Deep metal mining 1

EDI 1

Mitigation 1

Monitoring 1

PEDOT:PSS 1

Rockburst 1

Warning 1

ZEBRA 电池 1

cellular automaton模型 1

三峡工程 1

展开 ︾

检索范围:

排序: 展示方式:

Hollow carbon spheres and their noble metal-free hybrids in catalysis

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1380-1407 doi: 10.1007/s11705-021-2097-z

摘要: Hollow carbon spheres have garnered great interest owing to their high surface area, large surface-to-volume ratio and reduced transmission lengths. Herein, we overview hollow carbon sphere-based materials and their noble metal-free hybrids in catalysis. Firstly, we summarize the key fabrication techniques for various kinds of hollow carbon spheres, with a particular emphasis on controlling pore structure and surface morphology, and then heterogeneous doping as well as their metal-free/containing hybrids are presented; next, possible applications for non-noble metal/hollow carbon sphere hybrids in the area of energy-related catalysis, including oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, water splitting, rechargeable Zn-air batteries and pollutant degradation are discussed; finally, we introduce the various challenges and opportunities offered by hollow carbon spheres from the perspective of synthesis and catalysis.

关键词: hollow carbon spheres     functionalization     noble metal-free     catalysis    

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1986-2000 doi: 10.1007/s11705-023-2337-5

摘要: Breakage of the C–N bond is a structure sensitive process, and the catalyst size significantly affects its activity. On the active metal nanoparticle scale, the role of catalyst size in C–N bond cleavage has not been clearly elucidated. So, Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature, and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C–N bond hybridization patterns as reactants. Results showed a 13 times higher reaction rate for sp3-hybridized C–N bond cleavage than sp2-hybridized C–N bond cleavage, while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size increased. Different concentrations of terrace, step, and corner sites were found in different sizes of Ru nanoparticles. The relationship between catalytic site variation and C–N bond cleavage activity was further investigated by calculating the turnover frequency values for each site. This analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C–N bond cleavage activity, and the step atoms are the active sites for the C–N bond cleavage. When Ru nanoparticles are smaller than 1.9 nm, they have a strong adsorption effect on the reactants, which will affect the catalytic performance of the Ru catalyst. Furthermore, these findings were also confirmed on other metallic Pd/Pt catalysts. The role of step sites in C–N bond cleavage was proposed using the density function theory calculations. The reactants have stronger adsorption energies on the step atoms, and step atoms have d-band center nearer to the Fermi level. In this case, the interaction with the reactant is stronger, which is beneficial for activating the C–N bond of the reactant.

关键词: sp3/sp2-hybridized C–N bond     noble metal nanoparticle     catalytic active site     turnover frequency     DFT    

Shape/size controlling syntheses, properties and applications of two-dimensional noble metal nanocrystals

Baozhen An,Mingjie Li,Jialin Wang,Chaoxu Li

《化学科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 360-382 doi: 10.1007/s11705-016-1576-0

摘要: Two dimensional (2D) nanocrystals of noble metals (e.g., Au, Ag, Pt) often have unique structural and environmental properties which make them useful for applications in electronics, optics, sensors and biomedicines. In recent years, there has been a focus on discovering the fundamental mechanisms which govern the synthesis of the diverse geometries of these 2D metal nanocrystals (e.g., shapes, thickness, and lateral sizes). This has resulted in being able to better control the properties of these 2D structures for specific applications. In this review, a brief historical survey of the intrinsic anisotropic properties and quantum size effects of 2D noble metal nanocrystals is given and then a summary of synthetic approaches to control their shapes and sizes is presented. The unique properties and fascinating applications of these nanocrystals are also discussed.

关键词: two-dimension     noble metal     nanocrystal     surface plasmon     controllable synthesis    

Catalytic activity of noble metal nanoparticles toward hydrodechlorination: influence of catalyst electronic

Man ZHANG,Feng HE,Dongye ZHAO

《环境科学与工程前沿(英文)》 2015年 第9卷 第5期   页码 888-896 doi: 10.1007/s11783-015-0774-1

摘要: In this study, stabilized Pd, Pt and Au nanoparticles were successfully prepared in aqueous phase using sodium carboxymethyl cellulose (CMC) as a capping agent. These metal nanoparticles were then tested for catalytic hydrodechlorination toward two classes of organochlorinated compounds (vinyl polychlorides including trichloroethylene (TCE), tetrachloroethylene (PCE), and alkyl polychlorides including 1,1,1-trichloroethane (1,1,1-TCA), and 1,1,1,2-tetrachloroethane (1,1,1,2-TeCA)) to determine the rate-limiting steps and to explore the reaction mechanisms. The surface area normalized reaction rate constant, , showed a systematic dependence on the electronic structure (the density of states at the Fermi level) of the metals, suggesting that adsorption of organochlorinated reactants on the metal catalyst surfaces is the rate-limiting step for catalytic hydrodechlorination. Hydrodechlorination rates of 1,1,1-TCA and 1,1,1,2-TeCA agreed with the bond strength of the first (weakest) dissociated C-Cl bond, suggesting that C-Cl bond cleavage, which is the first step for dissociative adsorption of the alkyl polychlorides, controlled the catalytic hydrodechlorination rate. However, hydrodechlorination rates of TCE and PCE correlated with the adsorption energies of their molecular (non-dissociative) adsorption on the noble metals rather than with the first C-Cl bond strength, suggesting that molecular adsorption governs the reaction rate for hydrodechlorination of the vinyl polychlorides.

关键词: catalytic hydrodechlorination     electronic structure     metal nanoparticles     reaction mechanisms    

Copper nanoparticles/polyaniline-derived mesoporous carbon electrocatalysts for hydrazine oxidation

Tao Zhang, Tewodros Asefa

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 329-338 doi: 10.1007/s11705-018-1741-8

摘要:

Copper nanoparticles-decorated polyaniline-derived mesoporous carbon that can serve as noble metal-free electrocatalyst for the hydrazine oxidation reaction (HzOR) is synthesized via a facile synthetic route. The material exhibits excellent electrocatalytic activity toward HzOR with low overpotential and high current density. The material also remains stable during the electrocatalytic reaction for long time. Its good electrocatalytic performance makes this material a promising alternative to conventional noble metal-based catalysts (e.g., Pt) that are commonly used in HzOR-based fuel cells.

关键词: copper nanoparticles     mesoporous carbon     noble metal-free electrocatalyst     hydrazine oxidation reaction     polyaniline    

Zinc modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements for hydrogenation of nitroaromatics

《化学科学与工程前沿(英文)》 2022年 第16卷 第4期   页码 461-474 doi: 10.1007/s11705-021-2072-8

摘要: The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production, and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of nitroaromatics under mild reaction conditions. In this work, zinc-modified Ni-Ti catalysts (NixZnyTi1) were fabricated and applied for the hydrogenation of nitroaromatics hydrogenation. It was found that the introduction of zinc effectively increases the surface Ni density, enhances the electronic effect, and improves the interaction between Ni and TiO2, resulting in smaller Ni particle size, more oxygen vacancies, higher dispersion and greater concentration of Ni on the catalyst surface. Furthermore, the electron-rich Niδ obtained by electron transfer from Zn and Ti to Ni effectively adsorbs and dissociates hydrogen. The results reveal that NixZnyTi1 (Ni0.5Zn0.5Ti1) shows excellent catalytic performance under mild conditions (70 °C and 6 bar). These findings provide a rational strategy for the development of highly active non-noble-metal hydrogenation catalysts.

关键词: bimetal strategy     oxygen vacancy     non-noble metal catalyst     hydrogenation     aromatic nitro compounds    

Noble-metal-free cobalt hydroxide nanosheets for efficient electrocatalytic oxidation

Jie Lan, Daizong Qi, Jie Song, Peng Liu, Yi Liu, Yun-Xiang Pan

《化学科学与工程前沿(英文)》 2020年 第14卷 第6期   页码 948-955 doi: 10.1007/s11705-020-1920-2

摘要: Cobalt hydroxide has been emerging as a promising catalyst for the electrocatalytic oxidation reactions, including the oxygen evolution reaction (OER) and glucose oxidation reaction (GOR). Herein, we prepared cobalt hydroxide nanoparticles (CoHP) and cobalt hydroxide nanosheets (CoHS) on nickel foam. In the electrocatalytic OER, CoHS shows an overpotential of 306 mV at a current density of 10 mA·cm . This is enhanced as compared with that of CoHP (367 mV at 10 mA·cm ). In addition, CoHS also exhibits an improved performance in the electrocatalytic GOR. The improved electrocatalytic performance of CoHS could be due to the higher ability of the two-dimensional nanosheets on CoHS in electron transfer. These results are useful for fabricating efficient catalysts for electrocatalytic oxidation reactions.

关键词: electrocatalytic oxidation     cobalt hydroxide     nanosheet     water     glucose    

Hydro-pyrolysis of lignocellulosic biomass over alumina supported Platinum, Mo

Songbo He, Jeffrey Boom, Rolf van der Gaast, K. Seshan

《化学科学与工程前沿(英文)》 2018年 第12卷 第1期   页码 155-161 doi: 10.1007/s11705-017-1655-x

摘要: In-line hydro-treatment of bio-oil vapor from fast pyrolysis of lignocellulosic biomass (hydro-pyrolysis of biomass) is studied as a method of upgrading the liquefied bio-oil for a possible precursor to green fuels. The nobel metal (Pt) and non-noble metal catalysts (Mo C and WC) were compared at 500 °C and atmospheric pressure which are same as the reaction conditions for fast pyrolysis of biomass. Results indicated that under the pyrolysis conditions, the major components, such as acids and carbonyls, of the fast pyrolysis bio-oil can be completely and partially hydrogenated to form hydrocarbons, an ideal fossil fuel blend, in the hydro-treated bio-oil. The carbide catalysts perform equally well as the Pt catalyst regarding to the aliphatic and aromatic hydrocarbon formation (ca. 60%), showing the feasibility of using the cheap non-noble catalysts for hydro-pyrolysis of biomass.

关键词: bio-oil     pyrolysis     hydro-deoxygenation (HDO)     non-noble metal catalysts     hydro-treatment    

高压下铜-氢化合物体系的结构研究 Article

Jack Binns, Miriam Peña-Alvarez, Mary-Ellen Donnelly, Eugene Gregoryanz,Ross T. Howie, Philip Dalladay-Simpson

《工程(英文)》 2019年 第5卷 第3期   页码 505-509 doi: 10.1016/j.eng.2019.03.001

摘要:

理论和实验研究都表明,极端高压条件下氢气和众多金属或非金属所构成的二元体系化合物的物理性质显著增强,这使得含氢二元体系成为高压科学领域的重要研究对象。尽管氢气的化学性质活泼,但一些贵金属(如铜、银、金)依旧很难在常温常压下与氢气反应生成相应的金属氢化物,截至目前,没有任何贵金属与氢的摩尔比大于1的稳定化合物被报道。在本研究中,我们通过结合原位激光加热,在金刚石对顶砧压腔中通过氢气和金属铜单质反应成功合成了铜-氢二元化合物。通过对X射线衍射数据进行分析,我们探究了从常压到最高50 GPa压力范围内铜-氢体系的相行为和稳定性。该实验证实了前期理论预测的三个铜-氢化合物相:γ0-CuH0.15、γ1-CuH0.5和ε-Cu2H。更值得一提的是,该研究还通过对金刚石对顶砧腔体内部样品进行激光加热,合成了目前已知的室温下最高氢含量和稳定性的贵金属氢化物γ2-CuH0.65。该项研究加深了人们对于过渡金属-氢化合物体系的认知,同时,通过该实验合成的氢化物由于具有很高的含氢量,有望被设计成理想的储氢材料。

关键词: 高压     储氢材料     贵金属化学    

A ternary mechanism for the facilitated transfer of metal ions onto metal–organic frameworks: implications

《化学科学与工程前沿(英文)》   页码 1632-1642 doi: 10.1007/s11705-022-2187-6

摘要: Although metal–organic frameworks offer a new platform for developing versatile sorption materials, yet coordinating the functionality, structure and component of these materials remains a great challenge. It depends on a comprehensive knowledge of a “real sorption mechanism”. Herein, a ternary mechanism for U(VI) uptake in metal–organic frameworks was reported. Analogous MIL-100s (Al, Fe, Cr) were prepared and studied for their ability to sequestrate U(VI) from aqueous solutions. As a result, MIL-100(Al) performed the best among the tested materials, and MIL-100(Cr) performed the worst. The nuclear magnetic resonance technique combined with energy-dispersive X-ray spectroscopy and zeta potential measurement reveal that U(VI) uptake in the three metal–organic frameworks involves different mechanisms. Specifically, hydrated uranyl ions form outer-sphere complexes in the surface of MIL-100s (Al, Fe) by exchanging with hydrogen ions of terminal hydroxyl groups (Al-OH2, Fe-OH2), and/or, hydrated uranyl ions are bound directly to Al(III) center in MIL-100(Al) through a strong inner-sphere coordination. For MIL-100(Cr), however, the U(VI) uptake is attributed to electrostatic attraction. Besides, the sorption mechanism is also pH and ionic strength dependent. The present study suggests that changing metal center of metal–organic frameworks and sorption conditions alters sorption mechanism, which helps to construct effective metal–organic frameworks-based sorbents for water purification.

关键词: U(VI)     metal–organic frameworks     adsorption mechanism     metal node    

Sustainability of metal recovery from E-waste

Biswajit Debnath, Ranjana Chowdhury, Sadhan Kumar Ghosh

《环境科学与工程前沿(英文)》 2018年 第12卷 第6期 doi: 10.1007/s11783-018-1044-9

摘要:

Metal recovery techniques from electronic waste reported in literature.

Metal recovery processes followed in Industries from electronic waste.

Sustainability analysis of metal recovery processes from electronic waste.

关键词: E-waste     Metal recovery     Metal Recovery from E-waste (MREW)     Sustainability    

Optimizing iodine capture performance by metal–organic framework containing with bipyridine units

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 395-403 doi: 10.1007/s11705-022-2218-3

摘要: Radioactive iodine exhibits medical values in radiology, but its excessive emissions can cause environmental pollution. Thus, the capture of radioiodine poses significant engineering for the environment and medical radiology. The adsorptive capture of radioactive iodine by metal–organic frameworks (MOFs) has risen to prominence. In this work, a Th-based MOF (denoted as Th-BPYDC) was structurally designed and synthesized, consisting of [Th63-O)43-OH)4(H2O)6]12+ clusters, abundant bipyridine units, and large cavities that allowed guest molecules diffusion and transmission. Th-BPYDC exhibited the uptake capacities of 2.23 g·g−1 and 312.18 mg·g−1 towards I2 vapor and I2 dissolved in cyclohexane, respectively, surpassing its corresponding analogue Th-UiO-67. The bipyridine units boosted the adsorption performance, and Th-BPYDC showed good reusability with high stability. Our work thus opened a new way for the synthesis of MOFs to capture radioactive iodine.

关键词: metal–organic framework     iodine     adsorption     nuclear waste     environmental remediation    

Selective capture and separation of xenon and krypton using metal organic frameworks: a review

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1895-1912 doi: 10.1007/s11705-023-2355-3

摘要: Xenon and krypton are widespread useful noble gases in commercial lighting, lasers, electronics, and medical industry. At the same time, radioactive noble gases may proliferate from used nuclear fuel and diffuse in open atmospheres. Metal organic frameworks as hotspot porous materials for gases uptake and separation are considered to be potential solutions. In this review, we comprehensively summarized recent researches on metal organic frameworks for selective capture and separation of xenon and krypton. Particularly, we followed the aspects of different optimal design strategies, including optimal pore/cage size and geometry, open metal sites, ions (anions and cations), and polar functional groups for enhancing the xenon adsorption and separation performances. Meanwhile, a comparison of each strategy and the mechanisms of xenon/krypton separation were pointed out. The separation of krypton from gases mixtures by dual-bed systems was further discussed. Finally, some existing challenges and opportunities for possible real applications were proclaimed.

关键词: metal organic frameworks     xenon     krypton     selective separation     used nuclear fuel    

Liquid metal thermal hydraulics R&D at European scale: achievements and prospects

《能源前沿(英文)》 2021年 第15卷 第4期   页码 842-853 doi: 10.1007/s11708-021-0743-2

摘要: A significant role for a future nuclear carbon-free energy production is attributed to fast reactors, mostly employing a liquid metal as a coolant. This paper summarizes the efforts that have been undertaken in collaborative projects sponsored by the European Commission in the past 20 years in the fields of liquid-metal heat transfer modeling, fuel assembly and core thermal hydraulics, pool and system thermal hydraulics, and establishment of best practice guidelines and verification, validation, and uncertainty quantification (UQ). The achievements in these fields will be presented along with the prospects on topics which will be studied collaboratively in Europe in the years to come. These prospects include further development of heat transfer models for applied computational fluid dynamics (CFD), further analysis of the consequences of fuel assembly blockages on coolant flow and temperature, analysis of the thermal hydraulic effects in deformed fuel assemblies, extended validation of three-dimensional pool thermal hydraulic CFD models, and further development and validation of multi-scale system thermal hydraulic methods.

关键词: liquid metal     thermal hydraulics     Europe    

Localized high-concentration electrolytes for lithium metal batteries: progress and prospect

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1354-1371 doi: 10.1007/s11705-022-2286-4

摘要: With the increasing development of digital devices and electric vehicles, high energy-density rechargeable batteries are strongly required. As one of the most promising anode materials with an ultrahigh specific capacity and extremely low electrode potential, lithium metal is greatly considered an ideal candidate for next-generation battery systems. Nevertheless, limited Coulombic efficiency and potential safety risks severely hinder the practical applications of lithium metal batteries due to the inevitable growth of lithium dendrites and poor interface stability. Tremendous efforts have been explored to address these challenges, mainly focusing on the design of novel electrolytes. Here, we provide an overview of the recent developments of localized high-concentration electrolytes in lithium metal batteries. Firstly, the solvation structures and physicochemical properties of localized high-concentration electrolytes are analyzed. Then, the developments of localized high-concentration electrolytes to suppress the formation of dendritic lithium, broaden the voltage window of electrolytes, enhance safety, and render low-temperature operation for robust lithium metal batteries are discussed. Lastly, the remaining challenges and further possible research directions for localized high-concentration electrolytes are outlined, which can promisingly render the practical applications of lithium metal batteries.

关键词: high-concentration electrolyte     localized high-concentration electrolyte     lithium metal battery     solid electrolyte interphase     dendrite    

标题 作者 时间 类型 操作

Hollow carbon spheres and their noble metal-free hybrids in catalysis

期刊论文

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

期刊论文

Shape/size controlling syntheses, properties and applications of two-dimensional noble metal nanocrystals

Baozhen An,Mingjie Li,Jialin Wang,Chaoxu Li

期刊论文

Catalytic activity of noble metal nanoparticles toward hydrodechlorination: influence of catalyst electronic

Man ZHANG,Feng HE,Dongye ZHAO

期刊论文

Copper nanoparticles/polyaniline-derived mesoporous carbon electrocatalysts for hydrazine oxidation

Tao Zhang, Tewodros Asefa

期刊论文

Zinc modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements for hydrogenation of nitroaromatics

期刊论文

Noble-metal-free cobalt hydroxide nanosheets for efficient electrocatalytic oxidation

Jie Lan, Daizong Qi, Jie Song, Peng Liu, Yi Liu, Yun-Xiang Pan

期刊论文

Hydro-pyrolysis of lignocellulosic biomass over alumina supported Platinum, Mo

Songbo He, Jeffrey Boom, Rolf van der Gaast, K. Seshan

期刊论文

高压下铜-氢化合物体系的结构研究

Jack Binns, Miriam Peña-Alvarez, Mary-Ellen Donnelly, Eugene Gregoryanz,Ross T. Howie, Philip Dalladay-Simpson

期刊论文

A ternary mechanism for the facilitated transfer of metal ions onto metal–organic frameworks: implications

期刊论文

Sustainability of metal recovery from E-waste

Biswajit Debnath, Ranjana Chowdhury, Sadhan Kumar Ghosh

期刊论文

Optimizing iodine capture performance by metal–organic framework containing with bipyridine units

期刊论文

Selective capture and separation of xenon and krypton using metal organic frameworks: a review

期刊论文

Liquid metal thermal hydraulics R&D at European scale: achievements and prospects

期刊论文

Localized high-concentration electrolytes for lithium metal batteries: progress and prospect

期刊论文