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

《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    

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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    

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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    

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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    

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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    

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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    

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Highly uniform Ni particles with phosphorus and adjacent defects catalyze 1,5-dinitronaphthalene hydrogenation with excellent catalytic performance

Wei Xiong, Susu Zhou, Zeyong Zhao, Fang Hao, Zhihui Cai, Pingle Liu, Hailiang Zhang, Hean Luo

《化学科学与工程前沿（英文）》 2021年 第15卷 第4期   页码 998-1007 doi: 10.1007/s11705-020-1994-x

摘要： This work proposes a modified activated carbon support, with defects and heteroatoms (N,P-ACs) by nitrogen and phosphorus doping to load non-noble nickel to catalyze aromatic compound hydrogenation. The Ni/N,P-ACs-900 (prepared at 900 °C) showed promising catalytic activity in liquid-phase 1,5-dinitronaphthalene hydrogenation with a 1,5-diaminonaphthalene yield of 95.8% under the mild condition of 100 °C, which is comparable to the commercial Pd/C catalyst. The nitrogen species were burned off at 900 °C, causing more defects for nickel metal loading, facilitating the interaction between the supports and the nickel metal, and resulting in highly dispersed metal particles. The computational study of the nickel binding energy has been conducted using density functional theory. It exhibits that the defects formed by heteroatom doping are beneficial to nickel anchoring and deposition to form highly uniform nickel particles. The phosphorus species in combination with the defects are suitable for H adsorption and dissociation. These results reveal that the heteroatomic doping on the active carbon shows significant effects in the hydrogenation of the liquid-phase aromatic compounds. These findings could provide a promising route for the rational design of aromatic compound hydrogenation catalysts to significantly decrease the cost by instead using noble metal catalysts in the industry.

关键词： nitrogen and phosphorus doping     non-noble nickel catalyst     aromatic compounds hydrogenation    

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Metal-free, carbon-based catalysts for oxygen reduction reactions

Zhiyi Wu,Zafar Iqbal,Xianqin Wang

《化学科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 280-294 doi: 10.1007/s11705-015-1524-4

摘要： Developing metal-free, carbon-based catalysts to replace platinum-based catalysts for oxygen reduction reactions (ORRs) is an emerging area of research. In recent years, different carbon structures including carbon doped with IIIA-VIIA heteroatoms (C−M site-based, where M represents the doped heteroatom) and polynitrogen (PN) compounds encapsulated in carbon nanotubes (CNTs) (N−N site-based) have been synthesized. Compared to metallic catalysts, these materials are highly active, stable, inexpensive, and environmentally friendly. This review discusses the development of these materials, their ORR performances and the mechanisms for how the incorporation of heteroatoms enhances the ORR activity. Strategies for tailoring the structures of the carbon substrates to improve ORR performance are also discussed. Future studies in this area will need to include optimizing synthetic strategies to control the type, amount and distribution of the incorporated heteroatoms, as well as better understanding the ORR mechanisms in these catalysts.

关键词： oxygen reduction reaction     electrocatalysis     metal-free     carbon-based     polynitrogen    

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Current challenge and perspective of PGM-free cathode catalysts for PEM fuel cells

Gang WU

《能源前沿（英文）》 2017年 第11卷 第3期   页码 286-298 doi: 10.1007/s11708-017-0477-3

摘要： To significantly reduce the cost of proton exchange membrane fuel cells, platinum-group metal (PGM)-free cathode catalysts are highly desirable. Current M-N-C (M: Fe, Co or Mn) catalysts are considered the most promising due to their encouraging performance. The challenge thus has been their stability under acidic conditions, which has hindered their use for any practical applications. In this review, based on the author’s research experience in the field for more than 10 years, current challenges and possible solutions to overcome these problems were discussed. The current Edisonian approach (i.e., trial and error) to developing PGM-free catalysts has been ineffective in achieving revolutionary breakthroughs. Novel synthesis techniques based on a more methodological approach will enable atomic control and allow us to achieve optimal electronic and geometric structures for active sites uniformly dispersed within the 3D architectures. Structural and chemical controlled precursors such as metal-organic frameworks are highly desirable for making catalysts with an increased density of active sites and strengthening local bonding structures among N, C and metals. Advanced electrochemical and physical characterization, such as electron microscopy and X-ray absorption spectroscopy should be combined with first principle density functional theory (DFT) calculations to fully elucidate the active site structures.

关键词： oxygen reduction     fuel cells     cathode     nonprecious metal catalysts     carbon nanocomposites    

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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    

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Diffusion process in enzyme–metal hybrid catalysts

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 921-929 doi: 10.1007/s11705-022-2144-4

摘要： Enzyme–metal hybrid catalysts bridge the gap between enzymatic and heterogeneous catalysis, which is significant for expanding biocatalysis to a broader scope. Previous studies have demonstrated that the enzyme–metal hybrid catalysts exhibited considerably higher catalytic efficiency in cascade reactions, compared with that of the combination of separated enzyme and metal catalysts. However, the precise mechanism of this phenomenon remains unclear. Here, we investigated the diffusion process in enzyme–metal hybrid catalysts using Pd/lipase-Pluronic conjugates and the combination of immobilized lipase (Novozyme 435) and Pd/C as models. With reference to experimental data in previous studies, the Weisz–Prater parameter and efficiency factor of internal diffusion were calculated to evaluate the internal diffusion limitations in these catalysts. Thereafter, a kinetic model was developed and fitted to describe the proximity effect in hybrid catalysts. Results indicated that the enhanced catalytic efficiency of hybrid catalysts may arise from the decreased internal diffusion limitation, size effect of Pd clusters and proximity of the enzyme and metal active sites, which provides a theoretical foundation for the rational design of enzyme–metal hybrid catalysts.

关键词： enzyme–metal hybrid catalyst     internal diffusion     proximity effect     kinetic model    

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Transition metal-doped heteropoly catalysts for the selective oxidation of methacrolein to methacrylic

Yanxia Zheng,Heng Zhang,Lei Wang,Suojiang Zhang,Shaojun Wang

《化学科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 139-146 doi: 10.1007/s11705-015-1548-9

摘要： Heteropoly compounds with the general formula Cs M H P Mo VO (M= Fe, Co, Ni, Cu or Zn) and Cs Cu H P Mo VO ( = 0.1, 0.3 or 0.7) were synthesized and then used as catalysts for the selective oxidation of methacrolein to methacrylic acid. The effects of the transition metals on the structure and activity of the catalysts were investigated. FTIR spectra showed that the transition metal-doped catalysts maintained the Keggin structure of the undoped catalysts. X-ray diffraction results indicated that before calcination, the catalysts doped with Fe and Cu had cubic secondary structures, while the catalysts doped with Co, Ni or Zn had both triclinic and cubic phases and the Co-doped catalyst had the highest content of the triclinic form. Thermal treatment can decrease the content of the triclinic phase. NH temperature-programmed desorption and H temperature-programmed reduction results showed that the transition metals changed the acid and redox properties of the catalysts. The addition of Fe or Cu had positive effects on the activities of the catalyst which is due to the improvement of the electron transfer between the Fe or Cu and the Mo. The effects of the copper content on structure and catalytic activity were also investigated. The Cs Cu H P Mo VO catalyst had the best performance for the selective oxidation of methacrolein to methacrylic acid.

关键词： heteropoly compounds     transition metals     selective oxidation     methacrolein    

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Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton

《能源前沿（英文）》 doi: 10.1007/s11708-023-0907-3

摘要： Platinum (Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). However, their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading reduction. Based on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts, Pt single-atom catalysts (Pt SACs) as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this paper. The design thoughts and synthesis of various isolated, alloyed, and nanoparticle-contained Pt SACs are summarized. The single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the catalysts. To advance further research and development of Pt SACs for viable implementation in PEMFCs, various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis     Pt single-atom catalysts     conventional Pt-based catalysts     design thoughts and synthesis     metal-support interactions    

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Transition metal doped mesoporous titania with a crystalline framework as catalysts for oxidation of

YANG Zehui, OU Encai, WANG Yunan, PENG Li, WANG Jiaqiang, YIN Lihui

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 296-300 doi: 10.1007/s11705-008-0044-x

摘要： Transition metal M (M = Mn, Fe, Co, Ni, Cu, and Zn) doped mesoporous titania with a crystalline framework was employed as catalysts for the oxidation of -bromotoluene (PBT) to -bromobenzaldehyde (BBD) in acetic acid using aqueous hydrogen peroxide as oxidant. It was found that mesoporous TiO doped with those metals (Fe, Co and Ni) whose atomic radii are relatively smaller exhibited higher conversion rate of PBT. Among these catalysts, the Co/meso-TiO exhibited high substrate conversion and good product (-bromobenzaldehyde) selectivity plus it can be reused once with almost the same activity. The effect of different Ti/Co (molar) ratio on the activities of Co/meso-TiO was also investigated.

关键词： selectivity     conversion     -bromobenzaldehyde     aqueous hydrogen     oxidation    

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Metal salts with highly electronegative cations as efficient catalysts for the liquid-phase nitration

Shenghui Zhou, Kuiyi You, Zhengming Yi, Pingle Liu, Hean Luo

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 205-210 doi: 10.1007/s11705-017-1625-3

摘要： Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO to nitrobenzene under solvent-free conditions. Several salts including FeCl , ZrCl , AlCl , CuCl , NiCl , ZnCl , MnCl , Fe(NO ) ·9H O, Bi(NO ) ·5H O, Zr(NO ) ·5H O, Cu(NO ) ·6H O, Ni(NO ) ·6H O, Zn(NO ) ·6H O, Fe (SO ) , and CuSO were examined and anhydrous FeCl exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.

关键词： metal salts     electronegativity     nitrobenzene     NO2     catalytic nitration    

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标题 作者 时间 类型 操作

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

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

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

Highly uniform Ni particles with phosphorus and adjacent defects catalyze 1,5-dinitronaphthalene hydrogenation with excellent catalytic performance

Wei Xiong, Susu Zhou, Zeyong Zhao, Fang Hao, Zhihui Cai, Pingle Liu, Hailiang Zhang, Hean Luo

期刊论文

Metal-free, carbon-based catalysts for oxygen reduction reactions

Zhiyi Wu,Zafar Iqbal,Xianqin Wang

期刊论文

Current challenge and perspective of PGM-free cathode catalysts for PEM fuel cells

Gang WU

期刊论文

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

Tao Zhang, Tewodros Asefa

期刊论文

Diffusion process in enzyme–metal hybrid catalysts

期刊论文

Transition metal-doped heteropoly catalysts for the selective oxidation of methacrolein to methacrylic

Yanxia Zheng,Heng Zhang,Lei Wang,Suojiang Zhang,Shaojun Wang

期刊论文

Oxygen reduction electrocatalysis: From conventional to single-atomic platinum-based catalysts for proton

期刊论文

Transition metal doped mesoporous titania with a crystalline framework as catalysts for oxidation of

YANG Zehui, OU Encai, WANG Yunan, PENG Li, WANG Jiaqiang, YIN Lihui

期刊论文

Metal salts with highly electronegative cations as efficient catalysts for the liquid-phase nitration

Shenghui Zhou, Kuiyi You, Zhengming Yi, Pingle Liu, Hean Luo

期刊论文