CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 4
·6598-6605
·
IF 5.2
Wei Peng,Jianglei Chang,Bin Wang,Zhen Liu,Genshui Wang,Shuxiang Dong
The ultrahigh piezoelectric coefficient (d 33 ≥ 1000 pC/N) exhibited by piezoelectric Pb(Zr,Ti)O 3 (PZT) ceramics not only captivates researchers but also holds considerable practical value across various applications. While significant progress has been made in enhancing piezoelectricity of PZT-based ceramics, novel mechanisms need to be proposed to explain the piezoelectric behavior of new systems with ultrahigh d 33 . In this study, we initially employ LiNbO 3 as an additive to enhance the piezoelectric properties of the Pb(Ni 1 / 3 Nb 2 / 3 )O 3 –PbZrO 3 –PbTiO 3 ceramics. and the optimal performance is achieved by incorporating 1.5 mol% of LiNbO 3 into the system, resulting in an ultrahigh d 33 ∼1178 pC/N ( d 33 * ∼1560 p.m./V (@ E = 5 kV/cm)). The corresponding mechanism for this superior piezoelectric response involves the AB-site co-doping effect, especially the ( Li Pb ′ − Nb Zr / Ti ∙ ) defect dipoles formed by the introduction of LiNbO 3 . In particular, the addition of LiNbO 3 leads to a more uniform distribution of domain sizes, thereby further enhancing the ultrahigh piezoelectricity. These findings pave the way for a deeper under-standing of the origin of ultrahigh piezoelectric properties and make substantial contributions to the advancement of piezoelectric materials for practical applications in electromechanical devices.
研究领域:
材料科学
·
功能陶瓷
·
压电材料
·
固态物理
·
电子显微学
·
介电材料
·
无机非金属材料
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2015
·
IF 2.288
Zhiyong Mao,Jingjing Chen,Liang Sun,Qifei Lu,Dajian Wang
(Ba,Sr) 3 MgSi 2 O 8 :Eu 2+ , Mn 2+ phosphors with 430/505/660 nm tri-bands or 430/660 nm dual-bands emission were demonstrated in this work by controlling the appearence or not of green emitting intermediate phases, (Ba,Sr) 2 SiO 4 :Eu 2+ . Through varying the stoichiometric amount of SiO 2 in precursor, the coexistence of green emitting intermediate phase tended to be sensitive and diversified. Laser Microzone Raman spectrum was employed to look insight into the lattice stretch and the preferential occupation sites of Ba 2+ ions in Sr 3 MgSi 2 O 8 lattices. The local structure and the crystal field of Eu 2+ luminescent centers were found to be disturbed by distorted arrangement of cross-linked [MgO 6 ] octahedra and [SiO 4 ] tetrahedra. This mechanism approach provided some new insights to further understanding the adjustment strategy of green emitting intermediate phases in (Ba,Sr) 3 MgSi 2 O 8 :Eu 2+ , Mn 2+ phosphor potentially applied as red/blue dual-bands emitting or red/green/blue tri-bands emitting materials.
研究领域:
材料科学
·
无机化学
·
发光材料
·
固体物理
·
光电子学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Dewang Zeng,Yu Qiu,Min Li,Li Ma,Dongxu Cui,Shuai Zhang,Rui Xiao
Chemical looping redox cycle of oxygen storage materials offers a versatile platform to convert methane to value-added products in a clean and efficient manner. However, the highly dynamic nature of the oxygen diffusion process restrains the selective formation of the target products over a long reaction period. In this work, we show the oxygen storage materials-comprising of iron oxides and zirconium oxide support, with the nickel catalyst controllably deposited—that significantly enhanced the syngas selectivity. Mechanistic study indicated the oxygen releasing rate can be well controlled within a long reaction period by the specific spatial structure, demonstrating a new strategy to tune the oxygen diffusion in chemical looping process. Through the observed spatial effects, this work can be also extended to develop more oxygen storage materials for the other chemical looping applications, e.g. methane reforming, methane oxidative coupling, ethane oxidative dehydrogenation, etc .
研究领域:
催化化学
·
能源化学
·
材料化学
·
化学工程
·
多相催化
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·Vol. 43
·期 9
·2443-2452
·
IF 12.92
Yaojia Cheng,Haoqiang Song,Jingkun Yu,Jiangwei Chang,Geoffrey I.N. Waterhouse,Zhiyong Tang,Bai Yang,Siyu Lu
The sluggish kinetics of oxygen reduction reaction (ORR) hinders the commercialization of Zn-air batteries (ZABs). Manipulating the electronic structure of electrocatalysts to optimize the adsorption energy of oxygen-containing intermediates during the 4e − ORR offers a practical route toward improving ORR kinetics. Herein, we designed a novel ORR electrocatalyst containing Co single atoms and nanoparticles supported by carbon dots-derived carbon nanoflowers (Co SAs/NPs CNF). Co SAs/NPs CNF possessed a very high ORR activity ( E 1/2 of the Co SAs/NPs CNF catalyst is 0.83 V ( vs. RHE)), and outstanding catalytic performance and stability when used as the air-electrode catalyst in rechargeable ZABs (152.32 mW cm −2 , 1000.58 mWh g Zn −1 , and over 1300 cycles at a current density of 5 mA cm −2 ). The Co SAs and Co NPs cooperated to improve electron and proton transfer processes during ORR. Theoretical calculations revealed that the presence of adjacent Co NPs optimized the electronic structure of the isolated Co-N 4 sites, significantly lowering the energy barriers for the rate-determining step in ORR (adsorption of *OOH) and thereby delivering outstanding ORR performance. This work reveals that the combination of supported single-atom sites and metal nanoparticles can be highly beneficial for ORR electrocatalysis , outperforming catalysts containing only Co SAs or Co NPs.
研究领域:
电化学
·
纳米材料科学
·
能源化学
·
催化化学
·
先进电池技术
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 26
·8697-8705
·
IF 4.099
Yang Ding,Jie Liu,Ming Zeng,Xishu Wang,Junli Shi,Weili Wang,Yanru Miao,Xibin Yu
Rare earth (RE3+)-doped NaY(MoO4)2 nanocrystals are efficient materials for realizing multicolor emission, which plays an important role in displays, W-LEDs, solar cells and biolabeling. Up to now, research on the multicolor tuning properties of RE3+-doped NaY(MoO4)2 nanoparticles has mostly focused on traditional preparation routes such as the hydrothermal method and sol–gel process. However, the products obtained using these methods are usually large in size (on the micron/submicron scale) and agglomeration problems are inevitable. With the development of nano optoelectronic devices and bioluminescence labeling, there is an urgent need to find an efficient method to prepare nanoscale, monodispersed and NaY(MoO4)2:RE3+ nanocrystals (NCs) with good crystallinity and stronger emission properties. In this work, we demonstrate a simple, fast, reproducible and one-step synthesis of NaY(MoO4)2:Eu3+ NCs with sizes varying from 1–20 nm via a ligand-assisted reprecipitation strategy. The reaction mechanism and emission intensities of NaY(MoO4)2:Eu3+ NCs with various morphologies have been discussed in detail. Furthermore, Tb3+ and Eu3+ ion co-doped NaY(MoO4)2 NCs were also prepared, and various emission colors were obtained and tuned from red, orange-red, yellow and yellow-green to green. Energy transfer between the Tb3+ and Eu3+ ions in the NaY(MoO4)2 host matrix has also been demonstrated. Finally, a highly efficient and stable NaY(MoO4)2:0.05Tb,0.04Eu NC-based W-LED device was built, which indicates the promising future application for this material in the field of lighting. The tunable multicolour emission, ease of preparation and nanosize reveal that NaY(MoO4)2:RE3+ NCs have a potential application in full color displays and W-LEDs.
研究领域:
材料科学
·
纳米技术
·
光学材料
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jingsheng Xu,Zhiyuan Wang,Runguo Zheng,Hongyu Sun,Yanguo Liu,Junhua You
Ni-rich cathodes especially with Ni content over 90 % are promising next-generation cathode materials for advanced high energy lithium − ion batteries. However, in comparison with Ni ≤ 80 % Ni-rich cathodes, these ultrahigh Ni-rich materials face more severe challenges in terms of harmful H2 − H3 phase transformations and structural degradation during cycling. Herein, we present a robust surface structure composted of defect-rich disordered structures and LiF/Li 2 SiO 3 coating for stabilizing the ultrahigh Ni-rich cathode LiNi 0.96 Co 0.03 Mn 0.01 O 2 (NCM96) by modification with (NH 4 ) 2 SiF 6 . The surface disordered structures including Li/TM mixing, spinel, and rock salt structure play a crucial role in inhibiting the irreversible H2-H3 phase transition and reducing lattice volume changes by lattice coherence effect. Moreover, the disordered surface in collaboration with the co-coating restrains the rapid growth of surface rock salt phase into the bulk, enhancing structural stability. The modified sample NSF-0.5 delivers a capacity of 238 mAh/g at 0.1C and maintains a capacity retention of 88.5 % at 0.5C after 100 cycles in half cell as well as 82.3 % at 1C after 300 cycles in full cell, significantly superior to the NCM96. The findings provide a simple and cost-effective surface modification strategy to enhance the structural stability and electrochemical performance of ultrahigh nickel cathodes for high-energy density LIBs.
研究领域:
材料科学
·
电化学
·
能源存储
·
锂离子电池
·
固态化学
·
表面工程
·
电池材料
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2021
·Vol. 42
·期 10
·1798-1807
·
IF 8.271
Xiangyong Zhang,Tianying Liu,Ting Guo,Xueying Han,Zongyun Mu,Qiang Chen,Jiangmin Jiang,Jing Yan,Jiaren Yuan,Dezhi Wang,Zhuangzhi Wu,Zongkui Kou
Controllably mounting foreign atoms on the surfaces of earth-abundant electrocatalysts strongly improve their surface electronic properties for optimizing the catalytic performance of surficial sites to an unusual level, and provides a good platform to gain deep insights into catalytic reactions . The present work describes, employing ultrafine W 2 C nanoislands (average size: 2.3 nm) monodispersed on the N, P dual-doped carbon frameworks as a model system, how to regulate the atomic phosphorous-mounting effect on the surfaces of W 2 C to derive an active and stable P-mounting W 2 C (WCP) catalyst for both acidic and alkaline hydrogen evolution reaction (HER). Since in situ phosphorus substitution into carbon sites of preformed W 2 C nanoislands gradually proceeds from surfaces to solids, so that using a proper amount of phosphorus sources can readily control the surface mounting level to avoid the mass P-doping into the bulk. By this way, the activity per active site of WCP catalyst with robust stability can be optimized to 0.07 and 0.56 H 2 s −1 at –200 mV overpotential in acid and base, respectively, which reach up to the several-fold of pure-phase W 2 C (0.01 and 0.05 H 2 s −1 ). Theoretical investigations suggest that compared with solid P doping, the P mounting on W 2 C surface can more remarkably enhance its metallicity and decrease the hydrogen release barrier. This finding disclosed a key correlation between surface foreign atom-mounting and catalytic activity , and suggested a logical extension to other earth-abundant catalysts for various catalytic reactions .
研究领域:
材料化学
·
电催化
·
纳米材料
·
能源科学
·
表面科学
·
理论计算
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 20
·期 3
·2306251
·
IF 13.3
Muchun Guo,Ming Liu,Jianbo Zhu,Yuke Zhu,Fengkai Guo,Wei Cai,Yongsheng Zhang,QinYong Zhang,Jiehe Sui
Chemical bonds determine electron and phonon transport in solids. Tailoring chemical bonding in thermoelectric materials causes desirable or compromise thermoelectric transport properties. In this work, taking an example of CaMg 2 Bi 2 with covalent and ionic bonds, density functional theory calculations uncover that element Zn, respectively, replacing Ca and Mg sites cause the weakness of ionic and covalent bonding. Electrically, Zn doping at both Ca and Mg sites increases carrier concentration, while the former leads to higher carrier concentration than that of the latter because of its lower vacancy formation energy. Both doping types increase density-of-state effective mass but their mechanisms are different. The Zn doping Ca site induces resonance level in valence band and Zn doping Mg site promotes orbital alignment. Thermally, point defect and the change of phonon dispersion introduced by doping result in pronounced reduction of lattice thermal conductivity. Finally, combining with the further increase of carrier concentration caused by Na doping and the modulation of band structure and the decrease of lattice thermal conductivity caused by Ba doping, a high figure-of-merit ZT of 1.1 at 823 K in Zn doping Ca sample is realized, which is competitive in 1–2–2 Zintl phase thermoelectric systems.
研究领域:
材料科学
·
凝聚态物理
·
无机化学
·
能源材料
·
热电转换
✓ 已验证
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2011
·Vol. 32
·期 21
·1729-1734
·
IF 4.371
Juanping Hu,Xianfeng Wang,Bin Ding,Jinyou Lin,Jianyong Yu,Gang Sun
Electro-spinning/netting (ESN) as a cutting-edge technique evokes much interest because of its ability in the one-step preparation of versatile nano-fiber/net (NFN) membranes. Here, a controllable fabrication of polyurethane (PU) NFN membranes with attractive structures, consisting of common electrospun nanofibers and two-dimensional (2D) soap bubble-like structured nano-nets via an ESN process is reported. The unique nanoscaled NFN architecture can be finely controlled by regulating the solution properties and several ESN process parameters. The versatile PU nano-nets comprising interlinked nanowires with ultrathin diameters (5–40 nm) mean that the NFN structured membranes possess several excellent characteristics, such as an extremely large specific surface area, high porosity and large stacking density, which would be particularly useful for applications in ultrafiltration, special protective clothing, ultrasensitive sensors, catalyst support and so on.
研究领域:
材料科学
·
高分子化学
·
纳米技术
·
膜科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Ping He,Yu Zhang,Zhenguo Wang,Peng Min,Zhiming Deng,Lulu Li,Lvxuan Ye,Zhong-Zhen Yu,Hao-Bin Zhang
Graphene has been widely studied for its excellent properties of outstanding conductivity, strength , and flexibility. However, interlayer defects formed during the macroscopic assembly of graphene nanosheets will severely degrade the performance of graphene films. Herein, a strategy combined with trace carboxyl graphene oxide (GO), mild reduction, and chemical crosslinking is employed to minimize the interlayer defects for enhancing both the conductivity and mechanical strength of graphene films. The trace carboxyl feature of GO allows nanosheets to assemble orderly into highly oriented GO films . Subsequently, the mild chemical reduction preserves the highly oriented and packed microstructure. Coupling with further crosslinking by introducing conjugated molecules with pyrene terminal groups (1-pyrene butyric acid-1,6-hexane diamine, PHD) to provide extra π-π bonds, both the mechanical strength and conductivity of graphene films are improved to 548.4 MPa and 1.7 × 10 5 S m −1 , respectively. In addition, the graphene film with only ∼2 μm in thickness possesses an excellent electromagnetic interference shielding effectiveness (EMI SE) of ∼40 dB and a specific shielding effectiveness of up to 74 278 dB cm 2 g −1 in a wide frequency range of 8.2–40.0 GHz. Thus, this study provides an energy-saving fabrication route for mechanically strong, effective thermal management and EMI shielding films.
研究领域:
材料科学
·
纳米科技
·
高分子化学
·
功能材料
·
电磁屏蔽
·
热管理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 36
·19536-19545
·
IF 11.9
Gege Wang,Feifan Zhang,Caiyu Ma,Jianhua Yang,Xiaowei Chi,Yu Liu
Aqueous zinc metal batteries (AZMBs) as one of the next-generation energy storage technologies have attracted both academic and industrial attention due to their high safety, low cost, and high specific energy, yet are facing interfacial challenges at the electrolyte/anode interface, e.g. uneven physical diffusion of Zn2+ flux, severe chemical corrosion, and disordered electrochemical deposition behavior of the zinc metal anode. To address these issues, herein, we propose a facile and effective electrolyte modulating strategy to construct a physico-chemo-electrochemically coupled stable interface between the aqueous electrolyte and zinc anode. The aqueous electrolyte modified using a tiny amount of water-soluble ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) can form a positively charged organic EMIM+ adsorption layer and a protective inorganic Zn2+-conducting layer through the in situ decomposition of BF4− on the zinc anode surface, thus effectively homogenizing the Zn2+ diffusion flux and decreasing the chemical corrosion rate. Moreover, EMIM+ provides an electrostatic shielding layer, leading to the preferential and ordered electrodeposition of Zn2+ along the Zn (002). Benefiting from this physico-chemo-electrochemically multifunctional interfacial layer, the Zn//Zn symmetric cells achieve a considerably extended lifespan of up to 1200 h at 5 mA cm−2 and 5 mA h cm−2, and more than 450 h even at an ultrahigh current density and large deposition capacity (10 mA cm−2 and 10 mA h cm−2). Zn//Cu asymmetric cells also exhibit excellent reversibility with a high coulombic efficiency of 99.75%. Furthermore, the physically, chemically, and electrochemically stabilized interface enables the AZMB with a quinone-based cathode to offer high specific capacity (256.9 mA h g−1) and a decent capacity retention rate (83.9% after 300 cycles).
研究领域:
电化学
·
能源材料
·
界面科学
·
储能技术
·
材料化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2014
·Vol. 16
·期 37
·8910-8916
·
IF 3.858
Feng Ye,Hui Liu,Wenlai Huang,Jun Yang
Controlling the morphology of noble metal nanoparticles can be an effective way to produce nanomaterials with favourable properties. Herein, we report our study on the effects of diffusion rate and reaction kinetics on the morphology of a number of noble metal (Au, Ag, Pd, and Pt) nanoparticles. A glass reactor based on electrochemical reduction or photo-reduction has been designed to achieve control of diffusion and chemical reduction of the different noble metal precursors. The results show that the noble metal nanoparticles with flower-like, core–shell, or wheel-like morphologies could be obtained at a relatively high diffusion rate due to the presence of additional growth of metal precursors on the preformed metal nuclei, while at relatively low diffusion, the as-prepared noble metal nanoparticles are small and quasi-spherical due to the relatively fast reduction of metal precursors. The experimental observations are also confirmed qualitatively by kinetic Monte Carlo (kMC) simulations. Since diffusion and reaction kinetics are universal and key factors in the synthesis of nanomaterials, the findings in this work might provide an effective way to manipulate the morphology of nanomaterials for a given application.
研究领域:
纳米材料科学
·
物理化学
·
材料合成
·
胶体与界面化学
·
计算材料学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）