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Preparation and spectral properties of blue-to-UVB upconverting Y 2 O 3 :RE 3+ ,Gd 3+ (RE = Er, Ho) micro-/nano-phosphors

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Journal of Rare Earths 2025年

作者： Dechao Yu Xiaoshan Zhang Arend Zhang Xinxin Han Enhai Song Dawei Zhang Engineering Research Center of Optical Instrument and System The Ministry of Education Shanghai Key Laboratory of Modern Optical System University of Shanghai for Science and Technology Shanghai 200093 China Condensed Matter and Interfaces Debye Institute for Nanomaterials Science Utrecht University Princetonplein 5 3584 CC Utrecht The Netherlands MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials Guangxi University Nanning 530004 China State Key Laboratory of Luminescent Materials and Devices School of Materials Science and Engineering South China University of Technology Guangzhou 510641 China

Phototherapeutic applications gain more and more interests and require fundamental progresses in interdisciplinarity research, particularly a novel topical phototherapy using ultraviolet-B (UVB, ∼310 nm) upconverting phosphors. In this study, three synthesis methods with(out) sintering processes were implemented to obtain micro-/nano-size Y 2 O 3 :RE 3+ /Gd 3+ (RE = Er, Ho) particles using RE oxides (RE 2 O 3 ), RE-nitrates (RE(NO 3 ) 3 ) and RE-chlorides (RECl 3 ) as starting materials. Pumped by an OPO laser at wavelengths of 450 and/or 490 nm, blue-to-UVB upconversion with narrowband peak at 313 nm was effectively realized for all the Y 2 O 3 :RE 3+ /Gd 3+ powder phosphors. On basis of theoretical speculations and experimental data, a two-photon absorption process was proposed for the UVB upconversion of Y 2 O 3 :RE 3+ /Gd 3+ . Moreover, the involved energy transfer (ET) from RE 3+ to Gd 3+ , its back ET mechanisms as well as cross-relaxation between RE 3+ (RE = Er, Ho) ions were systematically treated versus the Er 3+ - or Ho 3+ -, and Gd 3+ -doping concentration. Note that the UVB upconversion intensity will decline severely as the particles become smaller to submicron and nanoscale, likely due to an increasing surface-to-volume ratio along with more surface defects appearance. All these results would greatly promote the development of novel blue-to-UVB upconverting materials, and their potential applications in topical phototherapy irradiated by blue light source.

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Robust Fano resonance in the photonic valley Hall states

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Physical Review A 2021年第2期103卷 023512-023512页

作者： Chang-Yin Ji Yongyou Zhang Bingsuo Zou Yugui Yao Key Lab of advanced optoelectronic quantum architecture and measurement (MOE) Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems and School of Physics Beijing Institute of Technology Beijing 100081 China China Academy of Engineering physics Mianyang Sichuan 621900 China Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials School of Physical science and Technology Guangxi University Nanning 530004 China

Rapidly developing photonics brings many interesting resonant optical phenomena, in which the Fano resonance (FR) always intrigues researchers because of its applications in optical switching and sensing. However, its sensitive dependence on environmental conditions makes it hard to implement in experiments. In this work we suggest a robust FR based on the photonic valley Hall insulators, immune to the system impurities. The robust FR is achieved by coupling the valley-dependent edge states with one double-degenerate cavity. The δ-type photonic transport theory we build reveals that this FR dates from the interference of the two transmissions that are attributed to the two cavity modes. We confirm that the induced Fano line shape of the transmission spectra is robust against the bending domain walls and disorders. Our work may provoke exciting frontiers for manipulating the valley transport and pave a way for the valley photonic devices such as optical switches, low-threshold lasers, and ultrasensitive sensors.

关键词： Photonic crystals Topological effects in photonic systems

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Selective Electrocatalytic Hydrodimerization of Acetylene to 1,3-Butadiene Over Neighboring Cu Dual Sites

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Angewandte Chemie - International Edition 2025年 e202505843页

作者： Bu, Jun Niu, Xinyue Li, Jinjin Bai, Rui Yuan, Menglei Zhang, Jian State Key Laboratory of Solidification Processing and School of Materials Science and Engineering Northwestern Polytechnical University Xi'an710072 China Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology and School of Chemistry and Chemical Engineering Northwestern Polytechnical University Xi'an710129 China

Selective electrocatalytic hydrodimerization of acetylene to 1,3-butadiene is a promising alternative to the energy-intensive naphtha steam cracking route, but remains a grand challenge due to competitive acetylene semihydrogenation and oligomerization. Herein, we profoundly investigate the underpinning structure–performance correlations between diverse nuclear number of Cu sites and acetylene hydrodimerization over benchmark Cu-MOFs electrocatalysts. The operando electrochemical Raman and Fourier transform infrared spectroscopies and theoretical simulations together reveal that single Cu site and double Cu sites are favorable for acetylene semihydrogenation and hydrodimerization, respectively. The as-designed neighboring Cu dual sites in trinuclear Cu3-MOF enable the adsorption of acetylene, subsequent C–C coupling of *C2H2 and *C2H3 intermediates into 1,3-butadiene as well as the desorption of 1,3-butadiene. As a result, the trinuclear Cu3-MOF affords a 1,3-butadiene selectivity of 91% and a high 1,3-butadiene production rate of 64 mmol g−1 h−1, which is about 2-fold and 20-fold higher than Cu2-MOF and Cu1-MOF. This work not only provides profound insights into the electrocatalytic mechanism of acetylene hydrodimerization but also guides the rational design of high-activity electrocatalysts. © 2025 Wiley-VCH GmbH.

关键词： Fourier transform infrared spectroscopy

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Preparation and Pseudo-capacitance Performance of NiCo2O4 Nanosheets

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Chemical Research in Chinese Universities 2019年第6期35卷 957-961页

作者： ZHOU Qi JIAO Sunzhi ZHENG Bin LI Zhiyang School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050P.R.China State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals^Lanzhou University of Technology Lanzhou 730050P.R.China

Ternary nickel cobaltite(NiCo2O4),as a promising electrode material for supercapacitors,has attracted increasing attention for its excellent electrochemical *** this study,novel NiCo2O4 nanosheets were rationally designed and prepared using dealloying process,followed by an oxidation *** as-prepared sample was characterized by microstructural and electrochemical techniques in view of its possible application in *** as-prepared sample exhibited high specific capacitance and excellent *** specific capacitance reached 663 F/g at 1 A/g and the rate capacitance high up to 73.6%when the current density increased from 1 A/g to 20 A/*** 5000 cycles of galvanostatic charge-discharge durability test at 4 A/g,the capacity retention rate was 82.1%.The results indicate that versatile dealloying can be used to prepare robust electrode for supercapacitor application.

关键词： Rapid-solidification Dealloying Nickel cobaltate Nanosheet Pseudo-capacitance

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Numerical Simulation and Experimental Verification of Dry Pressed MgTiO3 Ceramic Body during Pressureless Sintering

Research Square

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Research Square 2021年

作者： Wang, Jiang Ni, Yu Liu, Kai Du, Yanying Liu, Wei Wang, Zijian Huang, Shangyu Sun, Huajun State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan430070 China School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China School of Logistics Engineering Wuhan University of Technology Wuhan430070 China State Key Laboratory of Materials Processing and Die & Mould Technology School of Material Science and Engineering Huazhong University of Science and Technology Wuhan430074 China

To clarify the densification law of dry pressed MgTiO3 ceramic body during pressureless sintering, SOVS model modified with creep characteristics was embedded into finite element software Abaqus. The selected model can effectively express the grain boundary characteristics and densification mechanism. The change law of relative density, shrinkage rate, sintering stress and grain size of MgTiO3 cylindrical specimens were investigated by the above numerical simulation method. It showed that the average relative density of ceramic body rose from 60% to 97% and the shrinkage rate resepectively reached 17.28% and 11.99% in axial and radial direction. The average grain size increased from 1μm to 6 μm. In order to verify the accuracy of the simulation results, corresponding sintering experiments on cylindrical specimens were carried out to obtain actual sintering densities and shrinkage rates. It showed that the errors of relative density and shrinkage is below 5% and 2%. Grain growth trend was also basically consistent with the simulation results. After that, the above numerical simulation method was applied into the prediction of fabricating MgTiO3 filter with complex structure. Therefore, the present work provided a reliable numerical simulation method to predict the densification behavior of MgTiO3 ceramics during the pressureless sintering process, which was helpful to design and fabricate microwave dielectric products. © 2021, CC BY.

关键词： Titanium compounds

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Optimization of 3D Inlay Mode of "Z-Pins Like" V0.9-Si0.1 Rods and Their Improvement Effect on the Anti-Ablative Performance of C/C-ZrC-SiC

Research Square

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Research Square 2021年

作者： Tian, Tian Sun, Wei Qing, Xin Chu, Yuhao Chen, Haikun Liu, Yufeng Xiong, Xiang Zhang, Hongbo Central South University China State Key laboratory of Powder Metallurgy Central South University Changsha410083 China National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials Central South University Changsha410083 China Science and Technology on Advanced Functional Composites Laboratory Aerospace Research Institute of Material and Processing Technology Beijing100076 China

Neoteric "Z-pins like" vanadium0.9-silicon0.1 rods (V0.9-Si0.1 rods) as polybasic multiphase oxide compensators were prepared to improve the anti-ablation of C/C-ZrC-SiC over 2500 °C. The microstructure and improvement effect on the anti-ablation of different C/C-ZrC-SiC surface were investigated. Results show that the density of "Z-pins like" V0.9-Si0.1 rod was effectively improved after adding Si. When ablation time was less than 180 s, "Z-pins like" V0.9-Si0.1 rods perpendicular to non-woven cloth layer presented the best improvement of the anti-ablation performance by liquid/gaseous multicomponent oxide compensation. However, when ablation time was greater than 180 s, "Z-pins like" V0.9-Si0.1 rods perpendicular to non-woven cloth layer increased another harm that weaken the anti-ablative performance of C/C-ZrC-SiC, namely, the corrosion damage of oxide layer on the matrix surface caused by excessive oxide melt. Therefore, there is a best improvement of the anti-ablation performance of "Z-pins like" V0.9-Si0.1 rods parallel to non-woven cloth layer. © 2021, CC BY.

关键词： Silicon

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Experimental study on the oxidation behavior and microstructural evolution of NG-CT-10 and NG-CT-20 nuclear graphite

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Nuclear Science and Techniques 2019年第11期30卷 139-148页

作者： Wei Lu Ming-Yang Li Xiao-Wei Li Xin-Xin Wu Li-Bin Sun Zheng-Cao Li Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Collaborative Innovation Center of Advanced Nuclear Energy TechnologyInstitute of Nuclear and New Energy TechnologyTsinghua UniversityBeijing 100084China State Key Laboratory of New Ceramics and Fine Processing Key Laboratory of Advance Materials(MOE)School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

NG-CT-10 and NG-CT-20 are newly developed grades of nuclear-grade graphite from *** this study,their oxidation behaviors were experimentally investigated using thermal gravimetric *** evolution before and after oxidation was investigated using scanning electron microscope,mercury intrusion,and Raman *** apparent activation energy of NG-CT-10 nuclear graphite is 161.4 kJ/mol in a reaction temperature range of 550–700℃and that of NG-CT-20 is 153.5 kJ/mol in a temperature range of 550–650℃.The activation energy in the inner diffusion control regime is approximately half that in the kinetics control *** high temperatures,the binder phase is preferentially oxidized over the filler particles and small pores are generated in the *** new large or deep pores are generated on the graphite *** can diffuse along the boundaries of filler particles and through the binder phase,but cannot diffuse into the spaces between the nanocrystallites in the filler *** particles are oxidized starting at their outer surfaces,and the sizes of nanocrystallites do not decrease following oxidation.

关键词： Nuclear graphite Oxidation NG-CT-10 NG-CT-20 Activation energy

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Low-Cost Hydroxyacid Potassium Synergists as an Efficient In Situ Defect Passivator for High Performance Tin-Oxide-Based Perovskite Solar Cells

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Angewandte Chemie 2023年第25期135卷

作者： Wei Dong Chenpu Zhu Cong Bai Yue Ma Linfeng Lv Juan Zhao Fuzhi Huang Yi-Bing Cheng Jie Zhong Research Centre for Advanced Thin Film Photovoltaics State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 P. R. China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Foshan 528216 Guangdong Province P. R. China School of Automobile Engineering Wuhan University of Technology Wuhan 430070 P. R. China

Perovskite solar cells (PSCs) based on SnO 2 electron transport layers have attracted extensive research due to their compelling photovoltaic performance. Herein, we presented an in situ passivation of SnO 2 with low-cost hydroxyacid potassium synergist during deposition to optimize the interface carrier extraction and transport for high power conversion efficiency (PCE) and stabilities of PSCs. The orbital overlap of the carboxyl oxygen with the Sn atom alongwith the homogenous nano-particle deposition effectively suppresses the interfacial defects and releases the internal residual strains in the perovskite. Accordingly, a PCE of 24.91 % with a fill factor (FF) up to 0.852 is obtained for in situ passivated devices, which is one of the highest values for SnO 2 -based PSCs. Moreover, the unencapsulated device maintained 80 % of its initial PCE at 80 °C over 600 h, 100 % PCE at ambient conditions for 1300 h, and 98 % after one week maximum power point tracking (MPPT) under continuous AM1.5G illumination.

关键词： Chemical Bath Deposition Defect Passivation Electron Transport Layer Perovskite Solar Cells

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Tuning of electronic and optical properties of a predicted silicon allotrope: Hexagonal silicon h10-Si

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Physical Review B 2021年第12期104卷 125201-125201页

作者： Deju Zhang Haiyang Niu Yunguo Li Hong-Mei Huang Peng Jiang Yan-Ling Li School of Physics and Electronic Engineering Jiangsu Normal University Xuzhou 221116 China State Key Laboratory of Solidification Processing International Center for Materials Discovery School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China CAS Center for Excellence in Comparative Planetology University of Science and Technology of China Hefei 230026 China

The indirect band gap of the diamondlike silicon does not allow direct travel of electrons between valence band and conduction band edges, which has limited its application and performance in optoelectronic devices. Searching new silicon allotropes with highly tunable or direct band gap becomes more and more urgent with the increasing demand on clean energy. Here, we predict a silicon allotrope, h10-Si, which is an indirect-gap semiconductor with a band gap of about 0.96 eV. Furthermore, the electronic and optical properties exhibit a strong dependence on strain. In particular, the indirect band gap of the predicted silicon allotrope can be switched to a direct band gap at a uniaxial tensile strain of about 8% and the light absorption can be tuned continuously in a wide range of photon energy. Besides, the single-layer counterpart of this allotrope is confirmed to be dynamically stable and more stable in energy than silicene, endowing it with potential applications in nanoscale devices.

关键词： Band gap Electronic structure Strain Bethe-Salpeter equation Density functional theory

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Corrigendum to “In-situ study of dislocation coordinated plastic deformation mechanism in as-cast Ni 33 Co 40 Mn 27 medium entropy alloy” [924 (2025) 147818]

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materials Science and Engineering: A 2025年 925卷

作者： Qing Gao Biao Sang Weibing Wang Qi Wang Junqiang Ren Xuefeng Lu Jisen Qiao State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal School of Materials Science and Engineering Lanzhou University of Technology Lanzhou 730050 PR China School of Materials Science and Engineering Shaanxi University of Technology Hanzhong Shaanxi 723001 PR China College of Energy Engineering Huanghuai University Zhumadian 463000 PR China

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