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CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou Yang Dai Guoyao Yue Yiman Zhang Lulu Li Zhong-Zhen Yu Peng Min Hao-Bin Zhang 21 State Key Laboratory of organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

The SBA-15/SO_3H nanoreactor as a highly efficient and reusable catalyst for diketene-based,four-component synthesis of polyhydroquinolines and dihydropyridines under neat conditions

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Chinese Chemical Letters 2013年第5期24卷 401-403页

作者： Sadegh Rostamnia Fatemeh Pourhassan organic and Nano group(ONG) Department of ChemistryFaculty of ScienceUniversity of Maragheh

An efficient diketene ring-opening synthesis of polyhydroquinoline derivatives using SBA-15 sulfonic acid modified mesoporous substrates a green and reusable catalyst in a single-pot four-component coupling reaction of diketene,alcohol,enamine,and aldehydes is *** derivatives based on neat adduct of diketene,alcohols and aldehydes using SBA-15/SO_3H nanoreactor as catalyst via a four-component reactions are also *** advantages of the present method include the use of a small amount catalyst,simple procedure with an easy filterable work-up,waste-free,green and direct synthetic method with an excellent yield of products with efficient use of catalyst and a short reaction time.

关键词： SBA-15/SO3H Nanoreactor Diketene Polyhydroquinoline

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Reaction of Crossed Diperoxidation Between Cyclic Ketones and Alkyl Ketones

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Chemical Research in Chinese Universities 2002年第4期18卷 412-413页

作者： XU Wei-liang FU Cheng-ling organic chemistry group Huajiachi SectionZhejiang UniversityHangzhou 310029P.R.China

The reaction of crossed diperoxidation between the cyclic ketones and the alkyl ketones was investigated. The reaction is a competing in different ketones. It is slightly favorable to resulting in crossed ketone diper... 详细信息

关键词： Synthesis Crossed diperoxidation Crossed ketone diperoxide

Synthesis and Crystal Structure of 2-Amino-4- chloro-5-(4-methylbenzyl)-6-methylpyrimidine

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Chinese Journal of Structural chemistry 2007年第9期26卷 1005-1008页

作者：郭万成刘幸海陈沛全宋海滨李正名 Elemento-organic chemistry Institute State Key Laboratory of Elemento-organic Chemistry Nankai University

The title compound 2-amino-4-chloro-5-（4-methylbenzyl）-6-methylpyrimidine （C26H28Cl2N6, Mr = 495.44） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 14.892（7）, b = 6.129（3）, c = 14.889（7）A, β = 109.795（8）°, V = 1278.7（10）A^ 3, Z = 2, F（000） = 520, Dc = 1.287 g/cm^3, μ = 0.280 mm^-1, the final R = 0.0577 and wR = 0.1589 for 1357 observed reflections with I 〉 2σ（I）. A total of 6091 reflections were collected, of which 2257 were independent （Rint = 0.033）. The X-ray analysis reveals that the chlorine atom and methyl of the title compound are disordered.

关键词： synthesis crystal structure X-ray diffraction

Synthesis and Crystal Structure of Diethyl 5-Acetoxy-3-(4-chlorophenyl)- 4,5-dihydroisoxazol-5-yl-5-phosphonate

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Chinese Journal of Structural chemistry 2006年第12期25卷 1453-1456页

作者：尚志强陈茹玉黄有 State Key Laboratory of Elemento-organic chemistry Institute of Elemento-organic Chemistry Nankai University

The crystal structure of the title compound, diethyl 5-acetoxy-3-（4-chlorophenyl）-4,5- dihydroisoxazol-5-yl-5-phosphonate （C15H19CINO6P, Mr = 375.73）, has been synthesized by the treatment of nitrile oxides and l-acetyloxy-vinylphosphonate under very mild conditions in good yields, and determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 16.914（10）, b = 10.567（7）, c = 21.927（13） A, β = 110.249（11）°, V = 3677（4） A^3, Z = 8, Dc = 1.358 g/cm^3, F（000） = 1568,/l（MoKa） = 0.324 mm^-1）, S = 1.011, the final R = 0.0661 and wR = 0.1556. The X-ray analytic results showed that the dihedral angle between the phenyl group and the isoxazoline ring is 10.7°.

关键词： crystal structure isoxazolines phosphonate synthesis

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China chemistry 2025年第1期 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu Liu Yangyang Liu Hui Wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode