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Journal of Advanced Ceramics 2024年第2期13卷 247-254页

作者： Mingan Shi Shuyang Ma Wangsuo Xia Ying Wang Jinzi Yu Haitao Wu school of materials science and physics China University of Mining and TechnologyXuzhou 221008China school of Environment and material Engineering Yantai UniversityYantai 264005China

Novel Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.8)ceramics,designed by replacing Ce^(4+)with Yb^(3+)ions were prepared by conventional oxide reaction,and the structural stability of the cubic fluorite structure was assessed using lattice energy and ionic properties of Ce/Yb-O *** oxygen vacancy caused by unequal substitution,which played a decisive role in bond ionicity and lattice energy,was analyzed experimentally by XPS and also theoretically by first *** Yb_(x)Ce_(1-x)O_(2-0.5x) ceramics maintain a stable cubic fluorite structure when x≤0.47,corresponding to the minimum lattice energy of 4142 kJ/mol with the lowest ionicity as ƒ_(i)=87.57%.For microwave dielectric properties,when the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.4)ceramics are pure phase,the porosity-corrected permittivity is dependent on the bond *** Q×ƒ values are related to the lattice energy and grain *** temperature coefficient of resonance frequency has been analyzed using bond *** the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0.5-0.8)ceramics are multiple phases,the microwave dielectric properties are associated with the phase composition and grain growth.

关键词： structure stability bond ionicity oxygen vacancy electronic localization function(ELF)

A soft-contact hybrid electromagnetic–triboelectric nanogenerator for self-powered water splitting towards hydrogen production

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Nano Research 2024年第7期17卷 6567-6574页

作者： Fuxue Ma Yingjie Wu Shuge Dai Pei Lin Junlu Sun Lin Dong Key Laboratory of material physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450000China

The effective acquisition of hydrogen energy from the ocean offers a promising sustainable solution for increasing global energy ***,a self-powered high-efficient hydrogen generation system is proposed by integrating a triboelectric–electromagnetic hybrid nanogenerator(TEHG),power management circuit(PMC),and an electrolytic *** the wind triggering,as-fabricated TEHG can effectively convert breeze energy into electric energy,which demonstrates a high output current of 20.3 mA at a speed rotation of 700 rpm and the maximal output power of 13.8 mW at a load of 10 MΩ.Remarkably,asdesigned self-powered system can perform a steady and continuous water splitting to produce hydrogen(1.5μL·min^(−1))by adding a matching capacitor between the PMC and electrolytic *** the circuit,the capacitor can not only function as a charge compensation source for water splitting,but also stabilize the working *** other self-powered water splitting systems,the proposed system does not need catalysts or the complex electrical energy storage/release process,thus improving the hydrogen production efficiency and reducing the *** work provides an effective strategy for clean hydrogen energy production and demonstrates the huge potential of the constructed self-powered system toward carbon neutralization.

关键词： wind energy harvester hybrid nanogenerator energy conversion and management hydrogen energy production

Structure,electronic,and nonlinear optical properties of superalkaline M_(3)O(M=Li,Na)doped cyclo[18]carbon

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Chinese physics B 2024年第2期33卷 311-317页

作者：刘晓东卢其亮罗其全 school of physics and material science Anhui UniversityHefei 230601China Institute of Physical science and Information Technology Anhui UniversityHefei 230601China Department of Chemical physics University of Science and Technology of ChinaHefei 230026China

Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic *** have low ionization *** a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer *** this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not *** C_(18) ring still exhibits alternating long and short *** charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm.

关键词： superalkaline doped cyclocarbon structure and electronic properties nonlinear optical properties density functional theory(DFT)

Enhanced visible light absorption of Bi_(2)WO_(6)/SiO_(2) with abundant adsorbed oxygen for the degradation of organic pollutant

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Particuology 2024年第5期88卷 210-217页

作者： Yuanting Wu Xiaoying Wang Wenlong Zhong Shan Zhang school of material science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China

Heterogeneous photocatalysts exhibit high catalytic efficiency in the degradation of pollutants,but their stability and repeatability is not very good and requires high structural *** by nanosizing the pure Bi_(2)WO_(6)(BWO)photocatalyst without constructing a heterojunction,there is a significant improvement in its performance,with an enhancement effect of about 2.3 times(99.43%).The high photocatalytic degradation efficiency of the material can be attributed to the enhanced light absorption effect brought by the three-dimensional inverse-opal structure SiO_(2)(IS)and the abundant surface adsorbed oxygen generated after the formation of Si–O–W *** addition,the introduction of IS greatly increases the surface area of nanostructured BWO,which accelerates the charge transfer process,while the adsorbed oxygen promotes the participation of·O^(2−) in the photocatalytic reaction,thereby accelerating the consumption of photo-generated electrons and ultimately improving the separation of charge ***,the matched photonic bandgap further improves the absorption and utilization of light of the *** this work,we constructs Si–O–W bonds to obtain inverse-opal SiO_(2)/Bi_(2)WO_(6) with uniformly growth of pure phase nano BWO,which provides a feasible strategy for the preparation of high-performance pure-phase photocatalysts.

关键词： Bi_(2)WO_(6) SiO_(2) inverse-opal structure Photocatalysis Adsorbed oxygen

Insights into Formation and Li-Storage Mechanisms of Hierarchical Accordion-Shape Orthorhombic CuNb_(2)O_(6) toward Lithium-Ion Capacitors as an Anode-Active material

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Energy & Environmental materials 2024年第2期7卷 287-298页

作者： Chao Cheng Yunsheng Yan Minyu Jia Yang Liu Linrui Hou Changzhou Yuan school of material science and Engineering University of JinanJinan 250022China

The orthorhombic CuNb_(2)O_(6)(O-CNO)is established as a competitive anode for lithium-ion capacitors(LICs)owing to its attractive compositional/structural ***,the high-temperature synthesis(>900℃)and controversial charge-storage mechanism always limit its ***,we develop a low-temperature strategy to fabricate a nano-blocks-constructed hierarchical accordional O-CNO framework by employing multilayered Nb_(2)CT_(x)as the niobium *** intrinsic stress-induced formation/transformation mechanism of the monoclinic CuNb_(2)O_(6)to O-CNO is tentatively put ***,the integrated phase conversion and solid solution lithium-storage mechanism is reasonably unveiled with comprehensive in(ex)situ *** to its unique structural merits and lithium-storage process,the resulted O-CNO anode is endowed with a large capacity of 150.3 mAh g^(-1)at 2.0 A g^(-1),along with long-duration cycling ***,the constructed O-CNO-based LICs exhibit a high energy(138.9 Wh kg^(-1))and power(4.0 kW kg^(-1))densities with a modest cycling stability(15.8%capacity degradation after 3000 consecutive cycles).More meaningfully,the in-depth insights into the formation and charge-storage process here can promote the extensive development of binary metal Nb-based oxides for advanced LICs.

关键词： high-rate anodes lithium-ion capacitors lithium-storage mechanisms orthorhombic CuNb_(2)O_(6) phase transform

Raman signal enhancement for gas detection using a dual near-concentric cavities group

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Chinese Optics Letters 2024年第5期22卷 47-52页

作者：任一凡杨德旺孙颖欣许家旋刘硕芳陈月娥 Key Laboratory for Microstructural material physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China College of Ocean science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Effective methods are urgently required to optimize Raman spectroscopy technology to ameliorate its low detection ***,we superposed two near-concentric cavities to develop a dual near-concentric cavities group(DNCCG)to assess its effect on gas Raman signal intensity,signal-to-noise ratio(SNR),and limit of detection(LOD).The results showed that DNCCG generally had higher CO_(2) Raman signal intensity than the sum of two near-concentric ***,the noise intensity of DNCCG was not enhanced by the superposition of near-concentric ***,DNCCG increased the *** LOD for CO_(2) was 24.6 parts per *** could be an effective method to improve the detection capability of trace gases and broaden the dynamic detection range,which might aid the future development of innovative technology for multicomponent gas detection.

关键词： Raman spectroscopy gas detection sensitivity dual near-concentric cavities group

Effect of Bimodal Quasicrystal Phase on the Dynamic Recrystallization of Mg–Zn–Gd Alloy during High-Pressure Torsion

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1128-1134页

作者： Ping Li Shuangwu Xia Junfu Dong Liangwei Dai Zhicheng Luo Kemin Xue school of material science and Engineering Hefei University of TechnologyHefei230009China

The Mg–Zn–Gd alloy with quasicrystal icosahedral phase was processed by high-pressure torsion (HPT). The effect of bimodal I-phase on the dynamic recrystallization was analyzed by transmission electron microscopy. The results showed that the block I-phase can stimulate obvious particle-stimulated nucleation and dynamic recrystallization (DRX) grains were preferentially formed after HPT for 5 turns, while the granular I-phase only promoted the generation of sub-grains. The orientation relationship was determined as twofold//[1210] and fivefold//(0002)_(Mg). Moreover, after HPT for 9 turns, the DRX grains induced by block I-phase appeared to grow up and coarsened. Compared with block I-phase, the grains induced by granular I-phase presented much smaller size and distributed more homogeneous due to the strong pinning effect.

关键词： High-pressure torsion(HPT)-Quasicrystal phase Dynamic recrystallization Particle-stimulated nucleation Orientation relationship

Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： Jiang-jing Wu Xi-zhou Kai Chuang Guan Yu-tao Zhao school of material science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

Role of Crystal Seed in Aluminum Hydroxide Crystallization from Ammonia System with Added NH_(4)Al(SO_(4))_(2)·12H_(2)O

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Journal of Wuhan University of Technology(materials science) 2024年第4期39卷 945-953页

作者：王俊凯李来时 LIU Feng WANG Yuzheng 吴玉胜 school of material science and Engineering Shenyang University of TechnologyShenyang 110870China

A method to promote aluminum hydroxide crystal growth through pickling Al(OH)_(3)as seed in the ammonia system was proposed to overcome these *** experimental results show that,under the conditions of pickling time of 15 min,the acid concentration of 10%,the addition of 70 g/L pickling-Al(OH)_(3)seed,and the coarse granular Al(OH)_(3)products(d0.5=85.667)can be *** characterization results show that the phase of the product is gibbsite,consistent with the ***,the steps and ledges can be formed on pickling Al(OH)_(3)seed surface under the ammonia system,effectively promoting crystal *** crystal growth,the roughness of the crystal surface was first increased and then decreased,and the lamellar structure was deposited on the crystal seed *** final particles are approximately round,the surface is compact and *** growth of the product is surface reaction *** addition,the content of the AlO_(6)unit is increased and contributed to Al(OH)_(3)crystal growth.

关键词： reactive crystallization coarse-grained Al(OH)_(3) crystal seed crystal growth process

Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres

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Carbon Energy 2024年第8期6卷 90-104页

作者： Xuewen Jiang Qian Wang Limeng Song Hongxia Lu Hongliang Xu Gang Shao Hailong Wang Rui Zhang Changan Wang Bingbing Fan school of material science and Engineering Zhengzhou UniversityZhengzhouHenanChina Henan Key Laboratory of Aeronautical materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhouHenanChina school of materials science and Engineering Tsinghua UniversityBeijingChina

material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of *** alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)*** architecture,comprising SiO_(2)as the core,MXene as the intermediate layer,and MoS_(2)as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal *** complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2)***,the synergistic combination of SiO_(2)and MoS_(2)with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance ***,the core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 *** work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.”

关键词： core‐shell structure electromagnetic wave absorption multiloss mechanism SiO_(2)@MXene@MoS_(2)