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Journal of Rare Earths 2021年第4期39卷 434-439页

作者： J.M.Waikar R.K.More N.R.Lavande P.M.More Department of Chemistry Institute of Chemical TechnologyMatungaMumbai400019India

A series of magnesia doped CuOxCeO_(2-δ)catalysts were prepared by co-precipitation followed by impregnation method and investigated for CO *** manuscript is devoted to explaining the role of MgO for the formation of active species on the CuOxCeO_(2-δ)*** improvement in catalytic activity is ascribed to the formation of various active species due to the interaction of magnesia with CuOxCeO_(2-δ).The catalysts were characterized by PXRD,N_(2)adsorption,H_(2)-TPR,XPS,SEM,EDS and HRTEM *** Mg doped catalyst shows lattice expansion of ceria due to the formation of smaller Ce^(3+)species with oxygen *** Mg-O bond also takes part in CO activation and oxidation,which results in the increase of CO *** Mg doped CuOxCeO_(2-δ)catalyst shows improvement in low temperature activity compared with the CuOxCeO_(2-δ).

关键词： Adsorbed oxygen lattice expansion Low temperature oxidation Ce^(3+) Cu^(+) Rare earths

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Exploiting H-induced lattice expansion in β-palladium hydride for enhanced catalytic activities toward oxygen reduction reaction

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Journal of Materials Science & Technology 2022年第3期98卷 205-211页

作者： Yunwei Liu Zelin Chen Chang Liu Jinfeng Zhang Wenbin Hu Yida Deng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300372China State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China

We have developed an efficient strategy to synthesize an active and durable electrocatalyst of Pd hydride nanocubes(NCs).Instead of the traditional chemical method,the PdH_(0.43)NCs are firstly prepared via a hydrogen diffusion procedure,followed by hydrothermal synthesis of an amorphous CuO layer encapsulating the PdH_(0.43)NCs to prevent the hydrogen atoms from *** lattice expansion is demonstrated playing a pivotal role in the enhancement of their oxygen reduction reaction(ORR)activity and *** obtained PdH_(0.43)@CuO NCs catalysts exhibit an ORR mass activity of 0.18 A mg^(−1) at 0.90 V versus reversible hydrogen electrode in an alkaline medium,which is about five times higher than that of commercial Pt/*** durability tests show that there is only a 32 mV decay in halfwave potential even after 10,000 potential cycles,indicating the excellent stability of PdH_(0.43)@CuO *** functional theory(DFT)calculations also indicate that,compared to Pd,PdH_(0.43)has a lower limiting barrier to form OH−during the ORR *** present study illustrates the importance of lattice expansion caused by hydrogen and offers an available strategy to design highly efficient and durable Pdbased electrocatalysts for alkaline fuel cells.

关键词： lattice expansion Pd hydride Amorphous CuO Elecrocatalysis Oxygen reduction reaction

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YPO_4 nanocrystals: preparation and size-induced lattice symmetry enhancement

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Journal of Rare Earths 2008年第4期26卷 495-500页

作者：刘琼苏毅国于洪生韩炜 College of Physics Jilin University Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

YPO4 and Eu doped YPO4 nanocrystals were prepared via a simple hydrothermal method. The phase purity, rnicrostructure, surface absorbed water and luminescence properties were characterized with X-ray diffraction （XRD）, transmission electron microscopy （TEM）, fluorescence spectrum, infrared spectroscopy, Raman spectroscopy and thermogravimetry analysis（TGA）. Combined with XRD and TEM analysis, it was found that YPO4 nanocrystals crystallized into a single phase of tetragonal （141/amd） zircon structure. YPO4 nanocrystals showed a size reduction with the reaction temperature decreasing. Considering the XRD, IR and Raman results, a lattice expansion and the unit cell symmetry enhancement were observed with the particle size decreasing. A dipole to dipole interaction model was applied to investigate the relationship of the variation of microstrucmre and the particle size. The emission spectrum of Eu doped YPO4 nanocrystals was also presented and the emission bands were clearly ascribed to the f to f transitions of Eu^3＋.

关键词： hydrothermal lattice expansion symmetric enhancement blue shift luminescence rare earths

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Two-dimensional porous carbon derived from pollen with enlarged interlayer distance enhanced electrocatalytic oxidation of n-valeraldehyde to octane

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Nano Research 2024年第5期17卷 3455-3461页

作者： Meichun Qin Chaolong Liu Shouhen Xu Jianguo Tang Institute of Hybrid Materials National Center of International Joint Research for Hybrid Materials TechnologyNational Base of International Sci.and Tech.Cooperation on Hybrid MaterialsCollege of Materials Science and EngineeringQingdao UniversityQingdao266071China Department of Pharmaceutics School of PharmacyQingdao UniversityQingdao266071China

Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added ***,low-cost and readily available electrocatalysts with high current efficiency were urgently ***,two-dimensional porous carbon derived from pollen with enlarged interlayer distance was built by alkali activation method,applying in electrocatalytic n-valeraldehyde oxidation *** enlarged interlayer distance was verified by X-ray diffraction(XRD)and high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Electrocatalytic experiments consequences showed activated biomass derived carbon possessed a higher electrocatalytic activity and octane selectivity than unactivated *** tests and in situ infrared experiments demonstrated that enlarged interlayer distance was positively correlated with specific surface area of catalysts,large specific surface area provided abundant absorption sites,facilitated the adsorption for n-valeraldehyde,and further promoted the transformation of n-valeraldehyde to *** work also provides a new avenue for creating high-performance electrocatalysts in terms of lattice engineering.

关键词： biomass derived carbon lattice expansion high specific surface area upgrade of n-valeraldehyde

Novel hydrogen storage properties of palladium nanocrystals activated by a pentagonal cyclic twinned structure

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Nano Research 2015年第8期8卷 2698-2705页

作者： Huang Huang Shixiong Bao Qiaoli Chen Yanan Yang Zhiyuan Jiang Qin Kuang Xiaoyin Wu Zhaoxiong Xie Lansun Zheng State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials andDepartment of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Researchers appear to have neglected a special form of crystallites, pentagonal cyclic twinning, in which an obvious two-dimensional lattice expansion exists leading to novel physical-chemical properties associated with the changes in geometric and electronic structures. Using the storage and release of hydrogen in Pd nanocrystals as a probe, we have found that icosahedral pentagonal cyclic twinned Pd nanocrystals had distinct hydrogen storage properties, due to the two-dimensional lattice expansions, quite different from those of the octahedral single crystalline counterpart. In addition, the two-dimensional lattice expansion in pentagonal cyclic twinned Pd nanocrystals causes a change in electronic structure, which results in novel catalytic properties involving in situ formation of PdHx pentagonal cyclic twinned nanocrystals.

关键词： hydrogen storage lattice expansion tweed structure palladium nanoparticles

PHOTOCATALYTIC ACTIVITY OF LANTHANUM DOPING TiO2

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2001年第3期 32-35页

作者：岳林海水淼朱万良徐铸德

The photocatalytic activity of the mixtures of TiO\-2 with the rare earth oxide La was investigated. The study on the effect of the rare earth oxide content, calcinating temperature and calcinating time on the performance of the mixture revealed that sample treated under higher temperature and longer time had higher photoactivity than pure TiO\-2. The experimental results of polycrystalline X\|ray diffraction showed that the extent of the lattice expansion varied with the variation of calcinating temperature or time. It is suggested that this might be due to the variation of La content diffused into the TiO\-2 lattice. The La in the lattice may inhibit the recombinatin of photogenerated electron\|hole pairs and thus enhance the photoactivity.

关键词： La doping lattice expansion TiO\-2 photocatalytic activity