Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 15
·8893-8899
·
IF 10.7
Ziming Zhang,Zhiqiang Gao,Tingting Deng,Qingfeng Song,Lidong Chen,Shengqiang Bai
Mg3(Sb,Bi)2-based Zintl compounds have attracted lots of attention due to their high thermoelectric performance and good mechanical properties. However, thermally activated mobility, which is ascribed to the grain boundary scattering, greatly limits their practical use. In this work, we reveal the plasticity of Mg3(Sb,Bi)2-based compounds in the compressive strength test. The ab initio analysis indicates that this plasticity should be ascribed to the low slip barrier energy (∼580 mJ m−2), which is only one third of the cleavage energy (∼1600 mJ m−2). Based on this finding, we propose a cold-deformation procedure to elongate particles and to enhance texture, which successfully suppresses the grain boundary scattering. As a result, a high carrier mobility of 86.6 cm2 V−1 s−1 and a high power factor of 16.2 μW cm−1 K−2 in Mg3.1Bi1.5Sb0.49Te0.01 are obtained at room temperature. The plastic deformation capacity of Mg3(Sb,Bi)2 compounds provides a near-net-forming method to fabricate special-shaped devices at room-temperature, which will extend the application fields of thermoelectric techniques.
研究领域:
材料科学
·
凝聚态物理
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无机非金属材料
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热电转换
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固态物理化学
✓ 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
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电催化
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纳米材料
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能源科学
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表面科学
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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
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凝聚态物理
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无机化学
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能源材料
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热电转换
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Rui Huang,Hongye Wang,Cheng Tao,Hua Hao,Zhonghua Yao,Hanxing Liu,Minghe Cao
Thin film capacitors with large energy storage density and high breakdown strength are widely used in modern electronic fields. To solve the problems of interface effect and different polarization mechanism between matrix and fillers in conventional heterogeneous structure composite thin film capacitors, a new-type inorganic microcrystal-amorphous composite film of 0.92BaTiO 3 -0.08Bi(Ni 0.5 Zr 0.5 )O 3 (0.92BT-0.08BNZ) are prepared by sol–gel method. The amorphous matrix improving the breakdown strength is introduced into the film by adjusting preparation technology. Moreover, the nano-scale polar microcrystalline regions (fillers) are introduced and uniformly distributed in the amorphous matrix under various annealing temperatures. Through investigating the influence of different amorphous matrix and microcrystal trend on the dielectric and energy storage properties, it is found that synergistic effect between the polarized microcrystalline regions and the amorphous matrix are optimal at an annealed temperature of 550 ℃. The result shows that a high energy storage density of 103.7 J cm −3 and an efficiency of 88.3% are obtained under the electric field of 8.30MV cm −1 . Simultaneously, the excellent dielectric and energy storage stability is achieved in a wide temperature range of 20–200 °C. Conclusively, this microcrystal-amorphous composite film overcome the low energy storage capability and poor thermal stability of conventional composite films and provide a feasible way for preparing high energy storage performance films.
研究领域:
材料科学
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介电材料
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储能技术
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无机非金属材料
·
功能薄膜
✓ 已验证
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 45
·2403852
·
IF 13
Xinxin Wang,Chao Wang,Yajing Wang,Min Hao,Shengqiang Cui,Xudong Huang,Chunhui Wang,Jing Chen,Zhenxiang Cheng,Jianli Wang
N-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κ lat ) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag 2 Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag 2 Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems.
研究领域:
材料科学
·
凝聚态物理
·
能源材料
·
纳米结构工程
·
热电转换
✓ 已验证
DOI
高影响因子
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
·
2020
·Vol. 217
·期 6
·1900536
·
IF 1.759
Parisa Zeaiean Firouzabadi,Hajar Ghanbari,Nafiseh Mahmoudi,Seyed Mohammad Amin Haramshahi,Jafar Javadpour
Polymer-based composites are used for wound healing applications. This work aims to prepare an inorganic-polymer nanocomposite based on bentonite, poly(vinyl alcohol), and bacterial cellulose by electrospinning for wound healing. The nanocomposite is synthesized using a solution intercalation technique, with 1–2 wt% nanobentonite concentration variation. The effects of commercial and laboratory-synthesized nanobentonite as well as the extract of the green walnut shell (EGWS) are examined and characterized by different techniques. The addition of nanobentonite increases the average size of fibers and tensile strength up to 200 nm and more than 15 MPa, respectively, due to the presence of hydrogen bonding formed between the nanobentonite sheets and polymer matrix. By the addition of synthetic nanoclay and EGWS, moderate elongation and strength are achieved. The hydrophilicity shows a decreasing trend up to 2 wt% of commercial nanobentonite; however, the laboratory-synthesized nanobentonite is not significantly effective. Effects of extracts on the viability of cultured human adipose tissue–derived mesenchymal stem cells (ADSCs) are quantitated, where the samples containing 1–2 wt% of commercial nanobentonite have less toxicity than others. Antibacterial activity is tested against both Escherichia coli and Staphylococcus aureus bacteria according to the agar diffusion test for 72 h, in which EGWS-based mats exhibit strong antimicrobial activity.
研究领域:
生物材料学
·
组织工程
·
纳米医学
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再生医学
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药剂学
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微生物学
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高分子科学
✓ 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
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 50
·108538-108552
·
IF 5.8
Wang Yongqiang,Bai Yibo,Han Che,Li Zaimei,Lun Xiaowen,Zhang Conglu
Graphite-like carbon nitride (g-C 3 N 4 ) is favored for its excellent physicochemical properties. However, the high complexation rate of photogenerated carriers greatly limits its practical applications. Based on this, a novel CQDs-doped carbon nitride nanosheets composite (CNS/CQDs) was prepared and applied to the visible light–induced activation of peroxymonosulfate (PMS) for meloxicam (Mel) and tetracycline (TC) degradation. The photocatalytic degradation of Mel and TC were remarkably promoted in the CNS/CQDs+PMS+vis system. Mel photodegradation of 99.90% was achieved over 30 min with 20 mg CNS/CQDs and 20 mg PMS at pH11. And TC photodegradation of 95.97% was achieved over 45 min with 20 mg CNS/CQDs and 20 mg PMS at nature pH6.5. The TOC mineralization rates of Mel and TC were 75.49% and 52.00%, respectively. The transient photocurrent response and electrochemical impedance measurements (EIS) results indicated that the doping of CQDs could improve the charge transfer efficiency of pure g-C 3 N 4 , and CNS/CQDs had a low charge transfer resistance. Capture experiments and EPR tests explored the effective actives in the CNS/CQDs+PMS+vis system. Possible degradation pathways of Mel were also analyzed. This study provides valid residual drugs degradation under the dual conditions of visible light catalytic oxidation and persulfate oxidation, which will be a novel perspective for advanced oxidation technology to effectively remove organic pollutants from water.
研究领域:
环境科学
·
光催化化学
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水处理技术
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纳米材料
·
高级氧化工艺
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药物代谢
·
环境污染物降解
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·Vol. 43
·期 3
·2969-2973
·
IF 2.758
Bing Xie,Haibo Zhang,Hao Kan,Sisi Liu,Ming-Yu Li,Zeyu Li,Shuai Zhu,Shiyong Qiu,Shenglin Jiang
This work demonstrates a highly efficient method for large-scale synthesis of elongated BaTiO 3 nanowires via a novel stirring hydrothermal process. Compared with conventional hydrothermal reaction , one-dimensional (1D) lead-free BaTiO 3 nanowires can be realized at an even lower temperature with a shorter dwelling time. Results suggest that the mechanical force-driven stirring process improved the diffusion and surface reaction rate of BaTiO 3 nanocrystal growth in the solution phase, apparently, leading to the growth of the BaTiO 3 nanowires via an oriented attachment mechanism. Meanwhile, to the best of our knowledge, this method is also the first reported protocol which is capable to grow elongated BaTiO 3 nanowires with length up to tens of micrometers. This research outcome provides a promising option for low cost, high-throughput fabrication of 1D nanostructure in respect of mass-manufacturing.
研究领域:
材料科学
·
纳米科技
·
无机合成
·
功能材料
·
铁电材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 82
·52024-52029
·
IF 3.108
Xiao-Fen Sun,Zhongxia Wang,Wei-Qiang Liao,Peng-Fei Li,Jixing Gao,Yi-Yang Huang,Hai-Peng Chen,Heng-Yun Ye,Yi Zhang
In this paper, three new hybrid phase transition compounds, [Hmpy]CdBr3 (1, Hmpy = N-methylpyrrolidinuium cation), [Hmpy]2CdBr4 (2) and [Hmpy]3CdBr3·CdBr4 (3), were synthetized by means of regulating the ratio of reactants. Systematic characterizations consisting of variable temperature X-ray single crystal diffraction, differential scanning calorimetry (DSC) and dielectric measurements reveal that 1 with infinite one-dimensional (1D) [CdBr3]n− chains undergoes a phase transition around 278 K; 2 with isolated [CdBr4]2− tetrahedrons exhibits a high-temperature phase transition close to 367 K, accompanied by prominent switchable dielectric behavior. Interestingly, 1D [CdBr3]n− chains and isolated [CdBr4]2− tetrahedrons both exist in 3, associated with a phase transition at 320 K. The phase transitions in the three compounds are originated from the order-disorder transitions of the Hmpy cation. It is expected that our finding would promote the development of hybrid dielectric transition materials with adjustable properties.
研究领域:
材料化学
·
凝聚态物理
·
晶体工程
·
功能材料
·
介电材料
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2018
·
IF 2.207
Hongyu Shi,Na Li,Zhixia Sun,Tianqi Wang,Lin Xu
TiO 2 nanoparticles are commonly used as versatile precursors to make functional nanocomposite materials. However, the surface defects at grain boundaries of TiO 2 nanoparticles significantly affect the photoelectric properties of TiO 2 nanomaterials . In this work, we firstly prepared nanocomposites of TiO 2 and polyoxometalates (POMs) in which different POMs, including titanium-substituted POMs K 5 [PW 11 TiO 40 ] and K 7 [PW 10 Ti 2 O 40 ], are incorporated with TiO 2 nanoparticles so as to make an interface modification on grain boundaries of TiO 2 nanoparticles. Then the photoconductivities of the TiO 2 /POM nanocomposites were investigated through measurement of photocurrent responses, current-voltage curves, Mott-Schottky plots and surface photocurrent spectra. Compared with pure TiO 2 nanoparticles, TiO 2 /POM nanocomposites exhibit superior photoelectric properties, benefitting from the interface modification from different POMs. The gas sensing performance for acetone was also explored by use of the as-prepared photoconductive devices, and TiO 2 /PW 11 Ti exhibited a high gas sensing performance.
研究领域:
材料科学
·
纳米科技
·
半导体物理
·
传感器技术
·
光电子学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 108
·89290-89298
·
IF 3.84
Lili Wang,Byung Kee Moon,Sung Heum Park,Jung Hwan Kim,Jinsheng Shi,Kwang Ho Kim,Jung Hyun Jeong
A novel Sm3+-doped Sr2CaWO6 (SCWO) red phosphor, synthesized though a solid-state reaction, was reported. Its crystal structure was analyzed and refined via the Rietveld full-pattern fitting method based on XRD patterns. The CASTEP module of Materials Studio was used to investigate the band structure and density of states of the SCWO. The optical band gap was calculated through the UV-vis diffuse reflectance spectrum and compared with the value predicted by the DFT method. Raman spectra were recorded to confirm the substitution of cations by Sm3+ ions. The broad W–O charge transfer band and narrow excitation band at 406 nm from Sm3+ ions have comparable intensities in SCWO:Sm3+. After the introduction of charge compensators Li+, Na+ or K+, the intensity of the near-UV excitation band at 406 nm was almost twice as much as before. The profiles of the emission spectra under excitation into the charge transfer absorption and f–f transition of Sm3+ are different, and low-symmetry Sm3+ centres are preferentially excited via f–f absorption transitions. The intensity ratios of electronic, magnetic dipole-allowed transitions under different radiations show that the charge compensators can influence the chemical environment around Sm3+.
研究领域:
材料科学
·
固体化学
·
发光材料
·
晶体学
·
电子结构理论
·
无机功能材料
✓ 已验证
DOI
高影响因子