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Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu national engineering research center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Optimizing electronic structure through point defect engineering for enhanced electrocatalytic energy conversion

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Green Energy & Environment 2025年第1期10卷 109-131页

作者： Wei Ma Jiahao Yao Fang Xie Xinqi Wang Hao Wan Xiangjian Shen Lili Zhang Menggai Jiao Zhen Zhou Interdisciplinary research center for Sustainable Energy Science and engineering(IRC4SE2) School of Chemical EngineeringZhengzhou UniversityHenan450001China

Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic *** introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active *** optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of *** elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization ***,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse *** underscores the pivotal role of point defects in enhancing catalytic *** last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.

关键词： Point defect engineering Doping Vacancy Electrocatalysis Electronic structure

Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： Yi Qi Xueying Chen Bowen Liu Xuliang Lin Xueqing Qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine chemical engineering Jieyang center Guangdong Basic research center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

Effect of yttrium addition on water-gas shift reaction over CuO/CeO_2 catalysts

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Journal of Rare Earths 2009年第3期27卷 412-418页

作者：佘育生李雷詹瑛瑛林性贻郑起魏可镁 national engineering research center of chemical fertilizer catalysts Fuzhou University

This paper presented a study on the role of yttrium addition to CuO/CeO2 catalyst for water-gas shift reaction. A single-step co-precipitation method was used for preparation of a series of yttrium doped CuO/CeO2 catalysts with yttrium content in the range of 0-5wt.%. Properties of the obtained samples were characterized and analyzed by X-ray diffraction （XRD）, Raman spectroscopy, H2-TPR, cyclic voltammetry （CV） and the BET method. The results revealed that catalytic activity was increased with the yttrium content at first, but then decreased with the further increase of yttrium content. Herein, CuO/CeO2 catalyst doped with 2wt.% of yttrium showed the highest catalytic activity （CO conversion reaches 93.4% at 250 ℃） and thermal stability for WGS reaction. The catalytic activity was correlated with the surface area, the area of peak γ of H2-TPR profile （i.e., the reduction of surface copper oxide （crystalline forms） interacted with surface oxygen vacancies on ceria）, and the area of peak C2 and A1 （Cu^0→←Cu^2＋ in cyclic voltammetry process）, respectively. Besides, Raman spectra provided evidences for a synergistic Cu-Ovacancy interaction, and it was indicated that doping yttrium may facilitate the formation of oxygen vacancies on ceria.

关键词： CuO/CeO2 catalyst water-gas shift yttrium cyclic voltammetry rare earths

Effects of CeO_2 on structure and properties of Ni-Mn-K/bauxite catalysts for water-gas shift reaction

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Journal of Rare Earths 2008年第3期26卷 352-356页

作者：江莉龙叶炳火魏可镁 national engineering research center for chemical fertilizer catalysts Fuzhou University

Multiple-metal catalysts （Ni-Mn-Ce-K/bauxite） for Water-Gas Shift （WGS） reaction were prepared by impregnation, and the catalytic structure and properties were investigated by N2 physical, XRD, H2-TPR, and CO-TPD. The results indicated that the addition of 7.5% CeO2 improved the activity of the WGS reaction obviously, and also increased the specific surface area and pore volume of the catalysts. The addition of CeO2 decreases the reduction temperature, enhanced the adsorption and activation of H2O2, and improved the adsorption content of CO. Besides, active sites were not changed and the number of active sites on catalysts did not increase obviously.

关键词： impregnated water-gas shift bauxite CeO2 rare earths

InNi alloy-induced interface effect promoting the parallel electron transfer: improved photothermal catalytic CO2 hydrogenation

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Science China Chemistry 2025年

作者： Haoyu Zhang Yuhang Li Yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of chemical engineering and Technology Tianjin University Eco-environment and Resource Efficiency research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of Environmental Science and engineering Tianjin University Advanced Catalytic Materials research center School of Materials Science and Engineering Tianjin University research center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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A novel fused iron catalyst for ammonia synthesis promoted with rare earth gangue

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Journal of Rare Earths 2008年第5期26卷 711-716页

作者：俞秀金林炳裕林建新王榕魏可镁 national engineering research center of chemical fertilizer Catalyst Fuzhou University

Rare earth gangue, which mainly consists of mixtures of light rare earths such as lanthana, ceria, neodymium oxide and praseodymium oxide, was used as the promoter of fused iron catalysts for ammonia synthesis. The result showed that the activity of the catalyst promoted with rare earth gangue was comparable with those of commercial iron catalysts with high amount of cobalt. The role of rare earths was owed to their advantages for favoring the deep reduction of the main composite in catalyst, i.e., iron oxide. This fmding indicated that the use of rare earth gangue could decrease the content of cobalt or even completely replace cobalt, which was used to be regarded as unsub- stitutable promoters for high performance ammonia catalyst; therefore, the cost of fused iron catalysts would decrease significantly.

关键词： rare earth gangue promoter fused iron catalyst ammonia synthesis

Effect of rare earth on the performance of Ru/MgAl-LDO catalysts for ammonia synthesis

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Journal of Rare Earths 2018年第2期36卷 135-141页

作者： Jun Ni Baoqiang Jing Jianxin Lin Bingyu Lin Ziqi Zhao Lilong Jiang national engineering research center of chemical fertilizer Catalyst School of Chemical Engineering Fuzhou University

A series of MgAl-layered double oxides（LDO） doped with different rare-earth elements（Y, La, and Ce）were synthesized by the calcination of Mg-Al layered double hydroxides, and Ru, which were used to prepare ammonia synthesis catalysts. The as-obtained oxides and catalysts were characterized by XRD,TEM, TPD, TPR and XPS to understand their catalytic performances in ammonia synthesis. The H_2-TPR and HRTEM studies reveal that Ru/Y-LDO catalyst possesses more active Ru metal and small particle *** XPS demonstrates that the electronic interaction between Y and Ru metals is stronger, which can be tentatively explained by most of Y inserted into the hydrotalcites structure. CO_2-TPD demonstrates that Ru/Y-LDO catalyst shows stronger basic site densities than catalysts doped with Ce and La. Higher activity of the Ru/Y-LDO catalyst can be attributed to smaller particle size, more active metal（Ru） and strong Ru-support interaction.

关键词： Ru Ammonia synthesis Layered double oxide(LDO) Rare earth elements

Thermally stable lanthanum-doped mesoporous alumina as a stable support for palladium in catalytic oxidation of C_3H_8

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Journal of Rare Earths 2013年第11期31卷 1081-1084页

作者：江莉龙王玉玲王秀云罗永晋曹彦宁魏可镁 national engineering research center of chemical fertilizer Catalyst Fuzhou University

High thermally stable mesoporous alumina doped with lanthanum was synthesized using inorganic nitrates as precursors and employing pluronic P123 （P123, （EO20PO70EO20, EO=ethylene oxide, PO=propylene oxide）） as a structure-directing agent. After calcination at 400 oC, the resultant lanthanum doped alumina exhibited aγ-Al2O3 phase, which was the same as pure alumina. After the thermal treatment up to 1200 oC, La-doped Al2O3 generated only one phase ofθ-Al2O3 rather than two mixed phase ofθ-Al2O3 andα-Al2O3 and the surface area could still maintain 101 m2/g with a keeping pore volume of 0.66 cm3/g. The excellent thermal sta-bility was explained by the titration of strong Lewis acid sites ofγ-Al2O3 with the assistance of highly dispersed lanthanum species covering on alumina. Furthermore, the lanthanum modified mesoporous alumina was preliminarily employed as a stable support for Pd in the catalytic oxidation of C3H8.

关键词： lanthanum thermal stability mesoporous alumina calcination rare earths