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Dynamic confinement of SAPO-17 cages on the selectivity control of syngas conversion

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National Science Review 2022年第9期9卷 40-46页

作者： Haodi Wang Feng Jiao Yi Ding Wenjuan Liu Zhaochao Xu Xiulian pan Xinhe Bao State Key Laboratory of Catalysis 2011-Collaborative Innovation Center of Chemistry for Energy Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Physics University of Science and Technology of China Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences

The OXZEO(oxide-zeolite) bifunctional catalyst concept has enabled selective syngas conversion to a series of value-added chemicals and fuels such as light olefins,aromatics and gasoline.Herein we report for the first time a dynamic confinement of SAPO-17 cages on the selectivity control of syngas conversion observed during an induction period.Structured illumination microscopy,intelligent gravimetric analysis,UV-Raman,X-ray diffraction,thermogravimetry and gas chromatography-mass spectrometer analysis indicate that this is attributed to the evolution of carbonaceous species as the reaction proceeds,which gradually reduces the effective space inside the cage.Consequently,the difusion of molecules is hindered and the hindering is much more prominent for larger molecules such as C4+.As a result,the selectivity of ethylene is enhanced whereas that of C4+is suppressed.Beyond the induction period,the product selectivity levels off.For instance, ethylene selectivity levels off at 44% and propylene selectivity at 31 %,as well as CO conversion at 27%.The findings here bring a new fundamental understanding that will guide further development of selective catalysts for olefin synthesis based on the OXZEO concept.

关键词： syngas conversion OXZEO dynamic confinement zeolite diffusion

Modulating the CO methanation activity of Ni catalyst by nitrogen doped carbon

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Journal of Energy Chemistry 2018年第3期27卷 898-902页

作者： Yaping Lin pan Li Tingting Cui Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023Liaoning.China University of Chinese Academy of Sciences Beijing 100049China

Nitrogen doping has been proved to be an effective way to modify the properties of graphene and other carbon materials. Herein, we explore a composite with nitrogen doped carbon overlayers wrapping Si C substrate as a support for Ni（Ni/CN-Si C） and evaluate its effects on the methanation activity. The results show that both the activity and stability of Ni are enhanced. Characterization with STEM, XRD, XPS, Raman and H2-TPR indicates that nitrogen doping generates more defects in the carbon overlayers, which benefit the dispersion of Ni. Furthermore, the reduction of Ni is facilitated.

关键词： CO methanation Ni catalyst Carbon Nitrogen doping SiC

Nitrogen doped carbon catalyzing acetylene conversion to vinyl chloride

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Journal of Energy Chemistry 2014年第2期23卷 131-135页

作者： Xingyun Li Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Commercial production of vinyl chloride from acetylene relies on the use of HgCla as the catalyst, which has caused severe environmental problem and threats to human health because of its toxicity. Therefore, it is vital to explore alternative catalysts without mercury. We report here that N-doped carbon can catalyze directly transformation of acetylene to vinyl chloride. Particularly, N-doped high surface area mesoporous carbon exhibits a rather high activity with the acetylene conversion reaching 77% and vinyl chloride selectivity above 98% at a space velocity of 1.0 mL.min-l.g-1 and 200 ~C. It delivers a stable performa℃nce within a test period of 100h and no obvious deactivation is observed, demonstrating potentials to substitute the notoriously toxic mercuric chloride catalyst.

关键词： acetylene hydrochlorination vinyl chloride mercury-free N doped carbon

A highly active and stable Pd/B-doped carbon catalyst for the hydrogenation of 4-carboxybenzaldehyde

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Journal of Energy Chemistry 2019年第4期28卷 154-158页

作者： Kai Tie Xiulian pan Tie Yu pan Li Limin He Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Physics University of Science and Technology of China

Boron had been introduced into the structure of carbon material(BC), which was used as the support of Pd catalyst for hydrogenation of 4-carboxybenzaldehyde(4-CBA). The physical properties and chemical composition of the support and corresponding catalyst were characterized by N2 adsorption–desorption,Raman spectroscopy, inductively coupled plasma optical emission spectroscopy(ICP-OES), element analysis(EA), high-resolution transmission electron microscopy(HRTEM), CO-pulse chemisorption and X-ray photoelectron spectroscopy(XPS). The results demonstrate that Pd/BC catalyst exhibits a superior activity and good stability due to the more uniform dispersion of Pd nanoparticles, the presence of mesoporous structure and the enhanced interaction between Pd nanoparticles and the support, compared to carbon and N-doped carbon supported Pd catalysts(Pd/C and Pd/NC, respectively).

关键词： Heteroatom-doped carbon Palladium Catalytic hydrogenation

Facile filling of metal particles in small carbon nanotubes for catalysis

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Journal of Energy Chemistry 2013年第2期22卷 251-256页

作者： Hongbo Zhang Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

A versatile wet chemistry method is developed for filling of subnanometer sized metal particles in carbon nanotubes with a diameter smaller than 1.5 nm. As an example, we showed that a confined bi-component Pd-V catal... 详细信息

关键词： double-walled carbon nanotubes （DWCNTs） single-walled carbon nanotubes （SWCNTs） nanoparticles wet chemistry benzene hydroxyla-tion

SAPO-34 facilitates the formation of benzene,toluene and xylenes in direct syngas conversion over MnCrO_(x)-SAPO-34-ZSM-5

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Science China Chemistry 2024年第2期67卷 732-740页

作者： Shuchi Zhang Dengyun Miao Yi Ding Mengyuan Li Shujing Guo Yujuan Zhang Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China Shaanxi Yanchang Petroleum(Group)Co. Ltd.&Dalian Institute of Chemical Physics Xi’an Clean Energy(Chemical Industry)Research InstituteXi’an710000China

Direct conversion of syngas to aromatics over metal oxide and zeolite(OXZEO) composite catalysts is promising.However,the selectivity of more valuable products such as benzene,toluene and xylenes(BTX) is limited due to undesired secondary methylation of BTX.Herein,we report that the introduction of SAPO-34 into MnCrO_(x)-ZSM-5 catalyst enhances significantly the formation of BTX without sacrificing the aromatics selectivity.Under optimized conditions,the fraction of BTX in aromatics reaches 64.7% versus 28.9% over the catalyst without SAPO-34.A number of model reaction tests and characterizations reveal that SAPO-34 consumes partially the intermediates such as ketene,by converting them to light olefins.Thus,the methylation of BTX by ketene to heavy aromatics is inhibited over the external acid sites of ZSM-5,leading to an enhanced BTX selectivity in the products.This hybrid catalyst provides an efficient method for highly selective synthesis of BTX from syngas.

关键词： selective syngas conversion OXZEO aromatics BTX multi-functional catalysts

The effect of Al3+ coordination structure on the propane dehydrogenation activity of Pt/Ga/Al2O3 catalysts

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Journal of Energy Chemistry 2020年第2期29卷 93-99页

作者： Qinqin Yu Tie Yu Hongyu Chen Guangzong Fang Xiulian pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

The effect of the Al2O3 structure on the performance of Pt/Ga/Al2O3 catalysts is investigated for the direct dehydrogenation of propane. The study unveils that the structure of Al3+determines the bulk structure of catalysts, particularly a high content of coordinatively unsaturated Al3+sites(penta-coordinated Al3+,denoted as Al3+penta) could lead to a remarkably improved dehydrogenation activity of the catalyst. The bulk characterization reveals that the sufficient amount of Al3+pentain Al2O3 benefit the dispersion of Pt and Ga2O3 on the Al2O3 support. At the same time, TPR results reveal that the presence of Pt facilitates the reduction of Ga2O3, likely due to the hydrogen spillover between the well dispersed Pt and Ga2O3,which consequently enhances the synergistic function between Pt and Ga2O3 in the dehydrogenation of propane. Recyclability tests demonstrate that the dehydrogenation activity stabilizes after three cycles over the Pt/Ga/Al2O3 catalyst.

关键词： Dehydrogenation G32O3 Ai2O3 Coordinatively unsaturated

Enhanced hydrogen evolution reaction over molybdenum carbide nanoparticles confined inside single-walled carbon nanotubes

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Journal of Energy Chemistry 2019年第1期28卷 123-127页

作者： Tingting Cui Jinhu Dong Xiulian pan Tie Yu Qiang Fu Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Carbon nanotubes(CNTs) have shown as unique nanoreactors to tune the catalytic activity of confined nano-catalysts. Here we report that the catalytic performance of molybdenum carbide nanoparticles(MoC_x NPs) for the hydrogen evolution reaction(HER) process can be enhanced by encapsulation within single-walled carbon nanotubes(SWNTs) with a diameter of 1–2 nm. The catalyst with MoC_x NPs located on the interior surface of SWNTs(MoCx@SWNTs) exhibits a lower onset over-potential and a smaller Tafel slope than the one with MoC_x NPs attached on the exterior surface(MoCx/SWNTs). This is likely attributed to the much smaller particle size and the more reduced states of the confined MoC_x NPs, as well as the larger specific surface area of MoCx@SWNTs compared with Mo Cx/SWNTs. In addition, the electronic structure of the confined MoC_x NPs might be modified by the confinement effects of SWNTs, and hence the adsorption free energy of H atoms on the confined MoC_x NPs, which could also contribute to their higher performance. These results suggest that the SWNTs can be further explored for constructing novel catalysts with beneficial catalytic performance.

关键词： Single-walled carbon nanotubes Confined catalysis Molybdenum carbide Nanoparticles Hydrogen evolution reaction

Understanding nano effects in catalysis

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National Science Review 2015年第2期2卷 183-201页

作者： Fan Yang Dehui Deng Xiulian pan Qiang Fu Xinhe Bao State Key Laboratory of Catalysis iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Dalian Institute of Chemical PhysicsChinese Academy of Sciences

Catalysis, as a key and enabling technology, plays an increasingly important role in ields ranging from energy, environment and agriculture to health care. Rational design and synthesis of highly eicient catalysts has become the ultimate goal of catalysis research. hanks to the rapid development of nanoscience and nanotechnology, and in particular a theoretical understanding of the tuning of electronic structure in nanoscale systems, this element of design is becoming possible via precise control of nanoparticles’ composition, morphology, structure and electronic states. At the same time, it is important to develop tools for in situ characterization of nanocatalysts under realistic reaction conditions, and for monitoring the dynamics of catalysis with high spatial, temporal and energy resolution. In this review, we discuss coninement efects in nanocatalysis, a concept that our group has put forward and developed over several years. Taking the conined catalytic systems of carbon nanotubes, metal-conined nano-oxides and 2D layered nanocatalysts as examples, we summarize and analyze the fundamental concepts, the research methods and some of the key scientiic issues involved in nanocatalysis. Moreover, we present a perspective on the challenges and opportunities in future research on nanocatalysis from the aspects of:(1) controlled synthesis of nanocatalysts and rational design of catalytically active centers;(2) in situ characterization of nanocatalysts and dynamics of catalytic processes;(3) computational chemistry with a complexity approximating that of experiments; and (4) scale-up and commercialization of nanocatalysts.

关键词： nanocatalysis coninement carbon nanotubes graphene 2D materials inverse catalysts computational chemistry in situ characterizati