Journal Sciences News
The Surgeon
August 2018
C–H/C–F functionalization by E-selective ruthenium (II) catalysis
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Uttam Dhawa, Daniel Zell, Rongxin Yin, Shintaro Okumura, Masahiro Murakami, Lutz Ackermann

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August 2018
A regulatable oxidative valorization of furfural with aliphatic alcohols catalyzed by functionalized metal-organic frameworks-supported Au nanoparticles
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Liangmin Ning, Shengyun Liao, Xuguang Liu, Pengfei Guo, Zhenya Zhang, Haigang Zhang, Xinli Tong The oxidative upgrading of furfural (FUR) and aliphatic alcohols is an important way to produce desirable precursor of jet fuel or value-added furanic compound. Therein, developing a highly active catalytic system with switchable product selectivity still remains a challenge. In this work, we report a novel strategy on regulating the oxidative condensation and oxidative esterification of FUR with aliphatic alcohol in the presence of molecular oxygen. Firstly, Au@UiO-66 is prepared using different methods and employed as the catalyst for the oxidative valorization of FUR with methanol. It is found that the impregnation-reduction-H2 (I-H) method is the best where a 100% selectivity of methyl-2-furoate with a complete conversion was obtained using Au@UiO-66 as catalyst. Then, a series of metal-organic frameworks (MOFs) supported Au nanoparticles (Au@UiO-66-X) such as Au@UiO-66, Au@UiO-66-NH2, Au@UiO-66-NO2, Au@UiO-66-COOH and Au@UiO-66-NH3Cl have been prepared with I-H method and employed for oxidative valorization of furfural with ethanol. Experimental results showed that, in “FUR-ethanol-O2” system, the Au@UiO-66-X can efficiently regulate the oxidative condensation and oxidative esterification as two competitive reaction pathways. With Au@UiO-66-COOH as the catalyst, the oxidative condensation process is dominant in which 84.1% selectivity of furan-2-acrolein is attained; Meanwhile, the Au@UiO-66 is beneficial to the occurrence of oxidative esterification and generation of ethyl-2-furoate. At last, based on the catalyst characterization and the numerous control experiments, a possible catalytic reaction mechanism for conversion of FUR is proposed.

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August 2018
Highly selective electrocatalytic reduction of CO2 to formate over Tin(IV) sulfide monolayers
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Jia He, Xijun Liu, Haoxuan Liu, Zhe Zhao, Yi Ding, Jun Luo The electrochemical reduction of CO2 to fuels or valuable chemicals is an attractive method for satisfying the requirements of renewable energy storage and the artificial carbon cycle. In this study, SnS2 monolayers were applied as a robust catalyst for the electroreduction of CO2, enabling the efficient production of HCCO
August 2018
A new molecular pathway allows the chemoselective reduction of nitroaromatics on non-noble metal catalysts
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Reisel Mill
August 2018
Selective oxidation of ethanol over Ag, Cu and Au nanoparticles supported on Li2O/
August 2018
Control of nitrogen activation ability by Co-Mo bimetallic nanoparticle catalysts prepared via sodium naphthalenide-reduction
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Yuki Tsuji, Kiya Ogasawara, Masaaki Kitano, Kazuhisa Kishida, Hitoshi Abe, Yasuhiro Niwa, Toshiharu Yokoyama, Michikazu Hara, Hideo Hosono Co-Mo bimetallic nanoparticles (NPs) with various compositions were prepared on a CeO2 support (Co-Mo/CeO2) by sodium naphthalenide driven reduction. The Co-Mo/CeO2 catalyst exhibits much higher activity for ammonia synthesis than monometallic catalysts such as Co/CeO2 and Mo/CeO2, and the optimum activity is obtained at Co:Mo
August 2018
2D metal–organic-framework array-derived hierarchical network architecture of cobalt oxide flakes with tunable oxygen vacancies towards efficient oxygen evolution reaction
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Yuanjian Li, Huanwen Wang, Yuzhu Li, Qiang Wang, Debao Li, Rui Wang, Beibei He, Yansheng Gong The development of highly active dual-functional electrocatalysts, especially for oxygen evolution reaction (OER), is highly desirable to electrocatalyze water splitting for hydrogen production. Herein, a cobalt metal-organic frameworks (Co-MOFs) array is employed as the platform to fabricate oxygen-defect-rich Co3O4 flakes that are vertical grown on nickel foam substrates. This MOFs-derived Co3O4 arrays show a hierarchical interconnected porous flake network structure with tunable oxygen vacancies. The unique structural features obtained from an optimal hydrogenation condition render outstanding catalytic performance toward the oxygen evolution in alkaline media (an ultralow overpotential of 205
August 2018
Understanding methanol synthesis from CO/H2 feeds over Cu/CeO2 catalysts
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Leon G.A. van de Water, Sam K. Wilkinson, Richard A.P. Smith, Michael J. Watson Understanding copper-based methanol synthesis catalysts as a function of catalyst type and applied reaction conditions is an area of active industrial and academic research. In this work, results of a methanol synthesis study over a Cu/CeO2 catalyst using CO/H2 feeds are presented, using catalyst performance data combined with catalyst characterisation information (DRIFTS, XPS, TPR, XRD) obtained during start-up and under steady state methanol synthesis conditions. The results indicate that the active site and reaction mechanism for methanol synthesis over Cu/CeO2 are different from the conventional Cu/ZnO/Al2O3 catalyst, with CO, rather than CO2, being the carbon source for methanol. Fixed-bed micro reactors were employed to obtain catalyst performance data in discrete bed sectors using experimental spatial discretisation methods. Methanol synthesis activity over Cu/CeO2 from CO/H2 is preceded by transient CO2 formation, with the onset of methanol synthesis activity observed when the CO2 formation reaches its peak. Considerable differences between reactor bed sectors are observed during start-up, with CO2 formation, CO2 re-adsorption (as surface carbonates and formates), methanol formation and transient methanol decomposition occurring to different degrees and at different time scales. The interfaces of defective CeO2
August 2018
Palladium nanoparticles supported on core-shell and yolk-shell Fe3O4@nitrogen doped carbon cubes as a highly efficient, magnetically separable catalyst for the reduction of nitroarenes and the oxidation of alcohols
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Siyavash Kazemi Movahed, Noushin Farajinia Lehi, Minoo Dabiri The preparation of palladium nanoparticles (Pd NPs) supported on Fe3O4@nitrogen doped carbon (N-C) core-shell (C-S) and yolk–shell (Y-S) nanostructures is reported. The Fe3O4@N-C@Pd C-S nanostructures were synthesized by two different methods. The first method included two steps: (i) the annealing treatment of the Fe2O3@polydopamine (PDA) under a gas mixture of Ar/H2 flow and (ii) the decorating Pd NPs on the surface of annealed structures by sodium borohydride as a reducing reagent. The second method, the in-situ reduction of Fe2O3 and Pd2+ in the structure of Fe2O3@PDA@Pd2+ by annealing treatment under H2 flow as a reducing reagent led to Fe3O4@N-C@Pd C-S nanostructure. Additionally, the Y-S nanostructures were synthesized by using a HCl solution as an effective etching reagent to the partially etch the Fe3O4. Four types of Pd-based catalysts were tested in the selective reduction of p-nitrophenol (p-NP) to p-aminophenol (p-AP). Different catalytic activities were obtained through these catalysts. Furthermore, the reduction of nitroarenes and the oxidation of benzylic alcohols were also studies.

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August 2018
Operando Raman-online FTIR investigation of ceria, vanadia/ceria and gold/ceria catalysts for toluene elimination
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Qingyue Wang, King Lun Yeung, Miguel A. Ba
August 2018
Heterogeneous photo-catalysis from the perspective of the adsorbed state. The photo-oxidation of propan-2-ol to propan-2-one on rutile titanium dioxide
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Roger I. Bickley, Gerald R. Garside O2-titrations accompanying ESR, adsorption isotherm and TPD studies of well-crystallised powdered rutile provide insights into the nature of the reduced surface following adsorption of propan-2-ol at 300
August 2018
Zinc promoted alumina catalysts for the fluorination of chlorofluorocarbons
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Michael Jones, Graham J. Hutchings, David J. Willock, John Scott, Stuart H. Taylor A range of catalysts consisting of zinc impregnated
August 2018
Solution combustion synthesis of nano-catalysts with a hierarchical structure
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): G. Xanthopoulou, O. Thoda, S. Roslyakov, A. Steinman, D. Kovalev, E. Levashov, G. Vekinis, A. Sytschev, A. Chroneos The structure, composition, surface area and catalytic activity of Solution Combustion Synthesis (SCS) catalysts are all influenced by the conditions of preparation and in particular, the glycine concentration in the initial SCS solution. NMR was used to monitor the formation of glycine-nickel nitrate complexes in solution before SCS initiates, IR high speed temperature measurements have allowed to elucidate the mechanism of synthesis during SCS, dynamic X-ray analysis and thermogravimetric analysis have clarified the mechanisms of phase formation during SCS, BET analyses have shown the regularity of pore formation and SEM and TEM studies have indicated the regularities involved during microstructure formation. Regular three-dimensional (3D) flowerlike Ni-NiO hierarchical architectures were synthesized by SCS. The results have revealed a three-dimensional percolation network with hierarchical structure on the basis of nano-structured metal oxides and metals synthesized during SCS. Such hierarchically nanoporous catalysts have versatile structural properties such as increased surface area and large overall pore volume that can alleviate diffusional limitations of conventional nanocatalysts with solely microporous framework. This is important for liquid phase heterogeneous catalysis. These new insights provide a valuable capability for optimizing the selectivity and activity of SCS catalysis and will no doubt be of significant interest to a wide range of researchers working in catalysis and other fields.

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August 2018
Structure and activity of dispersed Co, Ni, or Mo sulfides for slurry phase hydrocracking of vacuum residue
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Sung-Ho Kim, Ki-Duk Kim, Donghun Lee, Yong-Kul Lee The effects of Co, Ni, or Mo precursors having different oil solubility and oxidation state on the slurry phase hydrocracking (HCK) of vacuum residue (VR) was investigated at 673
August 2018
Aerobic oxidation of alkanes on icosahedron gold nanoparticle Au55
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Aleksandar Staykov, Tetsuya Miwa, Kazunari Yoshizawa Aerobic oxidation of cyclohexane, propane, ethane, and methane to the corresponding alcohols was investigated over an Au55 gold nanoparticle with icosahedron symmetry using density functional theory. Reaction mechanisms were elucidated and activation barriers for catalytic CH bond cleavage and corresponding alcohols’ formation were estimated. Furthermore, on the basis of the reaction rate constants calculated for realistic reaction temperatures, the relative reaction rates for each alkane hydroxylation were discussed. The catalyst selectivity was investigated for the formation of primary and secondary alcohols. All reaction mechanisms for alkane hydroxylation are compared with the catalytic dissociation of dioxygen molecule over gold nanoparticle surface, which is an important precursor reaction for aerobic oxidation. We have further investigated overoxidation reaction mechanisms leading to formation of ketones. Our results are compared with experimental findings to provide important guidelines for the tuning of catalytic reactions towards the desired products and reaction conditions.

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August 2018
Optimizing Pd and Au-Pd decorated Bi2WO6 ultrathin nanosheets for photocatalytic selective oxidation of aromatic alcohols
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Renshan Wang, Benxia Li, Yi Xiao, Xueqin Tao, Xintai Su, Xiaoping Dong Ultrathin semiconductor nanosheets decorated with metallic nanoparticles (NPs) are promising in photocatalysis due to the multi-component interactions. The materials with a series of monometallic Pd and bimetallic Au-Pd NPs anchored on Bi2WO6 ultrathin nanosheets were synthesized and developed as photocatalysts for selective oxidation of aromatic alcohols to aromatic aldehyde. By optimizing the metallic contents, a typical sample of Au(0.25)Pd(0.25)-Bi2WO6 exhibited the highest photocatalytic activity among all the prepared photocatalysts including Au(0.5)-Bi2WO6, Pd(x)-Bi2WO6, Au(x)Pd(x)-Bi2WO6 (x represents the weight percentage of metal in the photocatalyst), along with the improved selectivity for producing benzaldehyde. The extended absorption in visible range, higher efficiency for the transfer and separation of photogenerated charge carriers, and the superior ability for generating active radicals of Au(0.25)Pd(0.25)-Bi2WO6 were demonstrated by DRS spectra, photoelectrochemical measurements, and ESR detection. The effect of the active species for selective oxidation of aromatic alcohols was proved to follow the order of h+
August 2018
Water activation by single Pt atoms supported on a Cu2O thin film
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Andrew J. Therrien, Kyle Groden, Alyssa J.R. Hensley, Alex C. Schilling, Ryan T. Hannagan, Matthew D. Marcinkowski, Alex Pronschinske, Felicia R. Lucci, E. Charles H. Sykes, Jean-Sabin McEwen Recent advances in single atom catalysis have sparked interest in their use as low-cost and high-efficiency catalysts in a wide variety of reactions. One such reaction that has been heavily studied with single atom catalysts is the water gas shift reaction. In addition, water participates in a rich variety of other industrially important catalytic processes, such as steam reforming reactions. However, much debate surrounds the structure and activity of single atoms toward water gas shift chemistry. By taking a model study approach, we determine the influence of atomically dispersed Pt atoms on the activation of water. Using a thin film Cu2O/Cu(1
August 2018
Effects of divalent metal ions of hydrotalcites on catalytic behavior of supported gold nanocatalysts for chemoselective hydrogenation of 3-nitrostyrene
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Yuan Tan, Xiao Yan Liu, Lin Li, Leilei Kang, Aiqin Wang, Tao Zhang The effect of the divalent metal ions on the hydrotalcite (HT) (MAl-HT; M
August 2018
PdRu alloy nanoparticles of solid solution in atomic scale: Size effects on electronic structure and catalytic activity towards electrooxidation of formic acid and methanol
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Xiongwu Kang, Kanghua Miao, Zhiwei Guo, Jiasui Zou, Zhenqing Shi, Zhang Lin, Jie Huang, Shaowei Chen It has been challenging to synthesize palladium (Pd) and ruthenium (Ru) alloy nanoparticles of solid solution in atomic scale, thus preventing us to study the size effect on the catalytic activity. Here we reported the synthesis of PdRu alloy nanoparticles through polyol reduction method, with the size from 6.0 to 16.6
August 2018
On the role of water in selective hydrogenation of cinnamaldehyde to cinnamyl alcohol on PtFe catalysts
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Yihu Dai, Xing Gao, Xiaofang Chu, Chunyang Jiang, Yao Yao, Zhen Guo, Chunmei Zhou, Chuan Wang, Hongming Wang, Yanhui Yang A series of carbon nanotube (CNT)-supported bimetallic PtFe nanoparticles were synthesized and employed as catalysts for hydrogenation of cinnamaldehyde in pure water. A synergy between water and bimetallic PtFe catalysts has allowed the efficiently selective production of cinnamyl alcohol. With the aid of water, an initial reaction rate of >1200
August 2018
Theoretical study on the reaction mechanism of carbon dioxide reforming of methane on La and La2O3 modified Ni(1
August 2018
Evolution of palladium sulfide phases during thermal treatments and consequences for acetylene hydrogenation
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Yanan Liu, Alan J. McCue, Junting Feng, Shaoliang Guan, Dianqing Li, James A. Anderson Unsupported, bulk phase palladium sulfide has been studied for the selective hydrogenation of acetylene. The sample underwent significant change during thermal pretreatments, the extent of which depends on temperature. Exposure to hydrogen at temperatures of 150
August 2018
Methanol oxidation on the Au(3
August 2018
Dioxygen activation routes in Mars-van Krevelen redox cycles catalyzed by metal oxides
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Stephanie Kwon, Prashant Deshlahra, Enrique Iglesia Catalytic redox cycles involve dioxygen activation via peroxo (OO
August 2018
Does hierarchical structure affect the shape selectivity of zeolites? Example of transformation of n-hexane in hydroisomerization
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Petr Sazama, Jana Pastvova, Dalibor Kaucky, Jaroslava Moravkova, Jiri Rathousky, Ivo Jakubec, Galina Sadovska The large mesoporous surfaces of hierarchical zeolites without confinement of the active sites leads to the question of whether the shape selectivity of these zeolites is essentially altered. The hydroisomerization of n-hexane to mono- and dibranched C6 isomers was carried out as a model reaction governed by the shape selectivity to obtain insight into the effects of the secondary mesoporous structure. A series of micro- and micromesoporous ZSM-5, MOR,
August 2018
Dopant segregation and CO adsorption on doped Fe3O4 (1
August 2018
High performance V2O5/MgF2 catalysts for gas-phase dehydrofluorination of 1,1,1,3,3-pentafluoropropane: Support-induced evolution of new active sites
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Jian-Dong Song, Tong-Yang Song, Ting-Ting Zhang, Yun Wang, Meng-Fei Luo, Ji-Qing Lu A series of supported V2O5/MgF2 catalysts were prepared and tested for dehydrofluorination of 1,1,1,3,3-pentafluoropropane (HFC-245fa) to synthesize 1,3,3,3-tetrafluoropropene (HFO-1234ze). The addition of V2O5 in MgF2 resulted in up to 5-fold increase in HFC-245fa conversion (from 19.2 to 95.2%) and much enhanced catalyst stability. Characterization results revealed that the dehydrofluorination initiated on the MgF2 support triggered the transformation of V2O5 to vanadium oxyfluoride (VOFx) species via the reaction between V2O5 and HF, and such species were responsible for the improved activity as they had much higher turnover frequencies (TOFs) than the MgF2 (0.762
August 2018
Surfactant modified platinum based fuel cell cathode studied by X-ray absorption spectroscopy
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): J. Melke, D. Dixon, L. Riekehr, N. Benker, J. Langner, C. Lentz, H. Sezen, A. Nefedov, C. W
August 2018
Significance of surface oxygen-containing groups and heteroatom P species in switching the selectivity of Pt/C catalyst in hydrogenation of 3-nitrostyrene
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Qifan Wu, Bin Zhang, Chao Zhang, Xiangchun Meng, Xinluona Su, Shan Jiang, Ruhui Shi, Yan Li, Weiwei Lin, Masahiko Arai, Haiyang Cheng, Fengyu Zhao The selectivity of 3-nitrostyrene (NS) hydrogenation over 0.5
August 2018
Crystallization of ATO silicoaluminophosphates nanocrystalline spheroids using a phase-transfer synthetic strategy for n-heptane hydroisomerization
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Tao Yue, Wei Liu, Liyuan Li, Xiaoling Zhao, Kake Zhu, Xinggui Zhou, Weimin Yang Changing size and shape of zeolitic crystals brings about enhanced diffusion properties and related promotion of catalytic performances. This work puts forward a phase-transfer synthetic strategy to generate ATO nanocrystalline silicoaluminophosphates spheroids under tumbling crystallization using aluminum isopropoxide dissolved in toluene and other ingredients (fumed silica/phosphoric acid/Di-n-hexylamine) dissolved in water as precursors. Toluene and aqueous phase formed a Pickering emulsion like structure during hydrothermal crystallization. Highly uniform crystalline spheroids of weighted 55
August 2018
Dependence of the plasmonic activity of Au/TiO2 for the decomposition of 2-naphthol on the crystal form of TiO2 and Au particle size
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Shin-ichi Naya, Hiroaki Tada Gold nanoparticles (Au NPs) were loaded on rutile (R)- and anatase (A)-TiO2 with the mean size varied and the loading amount maintained constant by the heating temperature-varied deposition-precipitation technique. Loading Au NPs on R-TiO2 (Au/R-TiO2) dramatically enhances the plasmonic photocatalytic activity for the decomposition of 2-naphthol under visible-light irradiation (
August 2018
Ethene oxychlorination over CuCl2/
August 2018
An unexpected formation of a Ru(III) benzylidene complex during activation of a LatMet-type ring-opening polymerisation catalyst
Publication date: August 2018
Source:Journal of Catalysis, Volume 364 Author(s): Anna Gawin, Pawe
July 2018
Pd-catalyzed carbonylative
July 2018
Editorial Board
Publication date: July 2018
Source:Journal of Catalysis, Volume 363

July 2018
Copper catalyzed oxidative coupling of ortho-vinylanilines with N-tosylhydrazones: Efficient synthesis of polysubstituted quinoline derivatives
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Angula Chandra Shekar Reddy, Pazhamalai Anbarasan Efficient and general copper catalyzed oxidative cyclization of ortho-vinylaniline has been accomplished employing N-tosylhydrazone as coupling partner. Various substituted quinoline derivatives of biological importance were achieved in good to excellent yield. The important features are the high functional group tolerates, up-gradation to gram scale synthesis and possible one-pot synthesis of quinoline from corresponding carboxaldehyde. Synthetic potential of the obtained quinoline derivatives was demonstrated through CH bond functionalization reaction. Furthermore, preliminary mechanistic investigation revealed the possible generation of non-stabilized diazo compound and imine derivative as potential intermediates as well as copper catalyzed electrocyclic reaction and oxidative aromatization.

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July 2018
WOx supported on
July 2018
Dynamic kinetic resolution of amines by using palladium nanoparticles confined inside the cages of amine-modified MIL-101 and lipase
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Sen Xu, Meng Wang, Bo Feng, Xinchen Han, Zijie Lan, Huajun Gu, Hexing Li, Hui Li Dynamic kinetic resolution (DKR) of amines is an important strategy for the synthesis of chiral drugs and their building blocks; however, improving the matchability of metal-catalyzed racemization and enzymatic resolution is still a task. In this paper, Pd nanoparticles (NPs) were encapsulated inside the cages of ethylenediamine-grafted MIL-101 (ED-MIL-101), giving highly efficient catalysts (Pd/ED-MIL-101) for the racemization of primary amines. The racemization can be combined with lipase-catalyzed resolution in a one-pot DKR of rac-1-phenylethylamine leading to optically pure product (>99% ee value) with an excellent conversion and selectivity up to 99% and 93%, respectively, superior to other catalysts, such as Pd/MIL-101, Pd/MCM-41 and commercially available Pd/C. Furthermore, the heterogeneous chemoenzymatic catalyst combination can be recovered and recycled 8 times without significant loss of efficiency. The enhance catalytic performances were found to depend on the amine modification of MIL-101 that not only endows the surface of its cages with basic property, but also enables efficiently confining Pd NPs in the cages. In addition, the matchability of such chemoenzymatic catalyst combination can be further enhanced by conducting the DKR process under microwave irradiation.

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July 2018
Dipole effect on ethylene epoxidation: Influence of alkali metals and chlorine
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Matej Hu
July 2018
Robust nickel cluster@Mes-HZSM-5 composite nanostructure with enhanced catalytic activity in the DTG reaction
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Zhiyong Wen, Zhimin Li, Qingjie Ge, Yang Zhou, Jian Sun, Hadi Abroshan, Gao Li Isoparaffin-rich gasoline plays an essential role in the global energy consumption. In this regard, there have been extensive studies to prepare catalysts for efficient synthesis of isoparaffin-rich gasoline. In this paper, we report a protocol to incorporate Ni nanoclusters (NiNC) into mesoporous Mes-HZSM-5 zeolite for the synthesis of NiNC@Mes-HZ catalysts. The catalysts are prepared via impregnation of Ni6(PET)12 clusters into Mes-HZSM-5 zeolite, followed by annealing at 550
July 2018
Understanding of the structure activity relationship of PtPd bimetallic catalysts prepared by surface organometallic chemistry and ion exchange during the reaction of iso-butane with hydrogen
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Reem Al-Shareef, Moussab Harb, Youssef Saih, Samy Ould-Chikh, Manuel A. Roldan, Dalaver H. Anjum, Elodie Guyonnet, Jean-Pierre Candy, Deng-Yang Jan, Suheil F. Abdo, Antonio Aguilar-Tapia, Olivier Proux, Jean-Louis Hazemann, Jean-Marie Basset Well-defined silica supported bimetallic catalysts Pt100- x Pd x were prepared by Surface Organometallic Chemistry (SOMC) and Ionic-Exchange (IE) methods. For all investigated catalysts, iso-butane reaction with hydrogen under differential conditions led to the formation of methane and propane, n-butane, and traces of iso-butylene. The total reaction rate decreased with increasing the Pd loading for both catalysts series as a result of decreasing turnover rate of both isomerization and hydrogenolysis. In the case of Pt100- x Pd x (SOMC) catalysts, the experimental results in combination with DFT calculations suggested a selective coverage of Pt (1
July 2018
Efficient low-temperature hydrogenation of acetone on bimetallic Pt-Ru/C catalyst
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Zhao Yang, Wenhan Chen, Jinbao Zheng, Zhiqing Yang, Nuowei Zhang, Chuan-Jian Zhong, Bing Hui Chen Carbon supported Pt-Ru nano-alloy with multiple reactive sites exhibits unprecedentedly efficient performance in acetone hydrogenation at room temperature. Catalytic properties can be controllably regulated and optimized via performing the specific annealing treatment for the catalyst. The essential correlation between the variations in catalyst’s annealing conditions and the resultant variation in catalytic properties has been explored and discussed as a structure-function relationship. The combination of Pt and Ru sites exhibits enhanced catalytic activity compared with monometallic ones. Larger PtRu alloy particle size favors the rapid CO hydrogenation and the improvement of catalytic selectivity to isopropanol. Isopropyl ether generation is related to the Pt defect sites on the surface, which can be blocked though the catalyst’s oxidation treatment. The presence of surface metal-oxide species is beneficial to the performance enhancement, resulting from the synergetic behavior between metal-oxide sites and metallic sites on respectively activating the reactants. Moreover, 3-pentanone is used as a probe molecule to verify the structure-function relationship of catalytic low-temperature CO hydrogenation on PtRu/C.

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July 2018
Bifunctional ligands for Pd-catalyzed selective alkoxycarbonylation of alkynes
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Huimin Qi, Zijun Huang, Menglan Wang, Peiju Yang, Chen-Xia Du, Shu-Wei Chen, Yuehui Li Catalytic carbonylations of alkynes represent straightforward and atom-economic synthesis of
July 2018
Lanthanum vanadate catalysts for selective and stable methane oxybromination
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): V. Paunovi
July 2018
Magnesium oxide supported bimetallic Pd/Cu nanoparticles as an efficient catalyst for Sonogashira reaction
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Mohammad Gholinejad, Maedeh Bahrami, Carmen N
July 2018
Insights into the role of MgAl layered double oxides interlayer in Pt/TiO2 toward photocatalytic CO2 reduction
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Ruifeng Chong, Caihong Su, Yuqing Du, Yangyang Fan, Zhang Ling, Zhixian Chang, Deliang Li The representative TiO2 loaded with cocatalyst (e.g., Pt) have been used extensively for the photocatalytic CO2 reduction in solar-to-chemical energy conversion. However, it still suffers from low efficiency, due to the weak adsorption/activation of CO2. In this work, an MgAl layered double oxides (MgAl-LDO) was successfully introduced into the interface of Pt/TiO2, by in-situ deposition of MgAl layered double hydroxides and subsequent high temperature calcination. The structure, optical property and the photocatalytic activity for CO2 reduction of as-fabricated Pt/MgAl-LDO/TiO2 were experimentally investigated. Especially, the roles of MgAl-LDO during the CO2 reduction process were highlighted. It concluded MgAl-LDO possessed Lewis acidic and Lewis basic bifunctional roles that enhanced the performance of the photocatalytic CO2 reduction. The optimal yields of CO and CH4 of Pt/MgAl-LDO/TiO2 exhibited ca. 2 and 11 times as high as that of Pt/TiO2, respectively. The adsorption states of CO2 and the adsorbed species in the course of photoreduction of CO2 with H2O vapor on Pt/MgAl-LDO/TiO2 were examined by in-situ infrared spectroscopy. Monodentate carbonate (m-CO3 2
July 2018
Boosting photocatalytic water oxidation achieved by BiVO4 coupled with iron-containing polyoxometalate: Analysis the true catalyst
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Min Zheng, Xiaohu Cao, Yong Ding, Tian Tian, Junqi Lin In this work, BiVO4 is selected as effective light-harvesting material to replace conventional unstable dye-sensitized photosensitizer ([Ru(bpy)3]2+) that easily occurs photodecomposition during artificial photosynthetic system. The addition of an eleven iron-containing polyoxometalate (Fe11POM) as efficient cocatalyst illustrates a dramatically improved photocatalytic water oxidation performance compared with that of pure BiVO4. Through careful characterization and analysis of selected-area, highly selective in-situ photo-deposition of Fe11POM into ultrathin nanofilm on the decisive 110 facet of BiVO4 under ultrapure water is clearly observed, and an intimate connection between nanofilm and hole-rich 110 facet is obtained in favor of enhancing surface catalytic efficiency. The exquisite decoration of ultrathin nanofilm can be further clarified as FeOx decomposed from Fe11POM, which could effectively capture the photogenerated holes and suppress the recombination of electron–hole pairs for promoting water oxidation performance through fast interfacial hole transfer process.

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July 2018
Switch in photocatalytic reaction selectivity: The effect of oxygen partial pressure on carbon-carbon bond dissociation over hydroxylated TiO2(1
July 2018
Quality control for Ziegler-Natta catalysis via spectroscopic fingerprinting
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Paul Pletcher, Alexandre Welle, Aur

Computational insights into the catalytic role of the base promoters in ester hydrogenation with homogeneous non-pincer-based Mn-P,N catalyst
Publication date: July 2018
Source:Journal of Catalysis, Volume 363 Author(s): Chong Liu, Robbert van Putten, Pavel O. Kulyaev, Georgy A. Filonenko, Evgeny A. Pidko The reaction mechanism of ester hydrogenation catalyzed by a bidentate aminophosphine ligated manganese catalyst was studied by DFT calculations. Particular emphasize was placed on the role of the alkoxide base additives. The presence of such basic promoters as KO t Bu can improve the catalyst activity by lowering the activation barriers of H2 dissociation as well as the hydrogenation step. The promoting effect of KO t Bu on H2 activation is much stronger than that of tert-butoxides with other alkali metals, which is crucial for the catalyst regeneration from the deactivated Mn-alkoxide species in the resting state.

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