Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 23
·12429-12437
·
IF 14.511
Shuang Li,Yunxiang Hou,Di Li,Bo Zou,Qingtang Zhang,Yang Cao,Guodong Tang
SnSe is considered one of the most intriguing new thermoelectric materials. Polycrystalline SnSe offers a wide range of thermoelectric applications due to its facile synthetic processing and machinability. Herein, we have achieved a high average ZT of 0.8 as well as a high peak ZT of 1.86 in solution-synthesized porous Zn and Ga codoped SnSe nanosheets, generating a maximum energy conversion efficiency of 13.3%. High-density micro/nanopores are induced in the SnSe matrix, which are more effective for scattering phonons and reducing the thermal conductivity. The high density of micro/nanopores, nanosheet structure and dislocations contribute to an ultralow lattice thermal conductivity (0.157 W m−1 K−1 at 873 K). Meanwhile, Ga incorporation can induce band convergence and create resonance levels, producing a large Seebeck coefficient. Ga and Zn codoping contributes to a sharp increase in carrier concentration and an obviously increased electrical conductivity. The enhanced Seebeck coefficient and increased carrier concentration help in achieving a significant enhancement of the power factor over a wide temperature range in the porous Zn and Ga codoped SnSe nanosheets. Consequently, high thermoelectric performance is realized over a wide temperature range via the decoupling of electron–phonon transport in SnSe. This work opens up a great opportunity for designing prospective materials for thermoelectric applications with the aid of the solution synthesis route.
研究领域:
材料科学
·
凝聚态物理
·
纳米科技
·
能源材料
·
半导体物理
·
热电转换
·
无机功能材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 112
·111052-111059
·
IF 3.289
Yuemei Li,Rui Wang,Yanling Xu,Jianjun Zhou,Zhihua Liu,Xiaojing Yan,Li Ma
ZnO:Yb3+,Tm3+,Ga3+ up-conversion nanoparticles (UCNPs) with sizes of between 20 and 65 nm are synthesized by the hydrothermal method. The size of the nanocrystals is affected by different Ga3+ concentrations. The variation in size has influence on the particles' visible blue and red up-conversion (UC) emission. In this paper, X-ray powder diffraction results show different amounts of gallium substituting for Zn in the ZnO lattice. When the concentration of Ga3+ is 3 mol%, the resulting UCNPs exhibit strong UC emission, longer fluorescence lifetime and narrower band gap. Due to their adjustable size and UC fluorescence properties, ZnO:Yb3+,Tm3+,Ga3+ nanocrystals have broad prospects for future applications in the biomedical field.
研究领域:
材料科学
·
纳米医学
·
生物光子学
·
无机功能材料
·
分子影像
✓ 已验证
DOI
高影响因子
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
·
2018
·Vol. 215
·期 11
·1700905
·
IF 1.795
Shuping Deng,Decong Li,Liping Zheng,Yu Tang,Zhong Chen,Luqi Sun,Wenting Liu,Lanxian Shen,Shukang Deng
In this work, the effect of Cd and Sn atoms partly substitution for Zn on among crystal growth, thermal stability, mechanical, and electrical transport property in β-Zn 4 Sb 3 is reported. In a series of samples prepared from the atomic ratios of Zn:Sb:Cd:Sn = 4.4:3: x :3 ( x = 0.2, 0.4, 0.6, and 0.8). Carrier concentration of all samples varies from 4.52 × 10 19 to 6.42 × 10 19 cm −3 as carrier mobility changes from 58.27 to 67.93 cm 2 V −1 s −1 at room temperature. As a result, electrical transport properties of the samples are optimized by Cd Sn co-doped. The experimental density of all the samples varies from 6.26 × 10 3 to 6.34 × 10 3 kg m −3 consistent with the theoretical value. The weight loss and melting point of the sample are determined to discuss thermal stability in the heating process in air, indicating that the single crystals β-Zn 4 Sb 3 possess an excellent thermal stability and it is practical importance in the TE application at high temperature. Consequently, the maximal power factor of 1.70 × 10 −3 W m −1 K −2 is achieved at 540 K for the sample with initial Cd content x = 0.2, which is enhanced by 40% compared with the single-doping system in β-Zn 4 Sb 3 .
研究领域:
材料科学
·
热电材料
·
固体物理
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Aijia Wei,Wen Li,Qian Chang,Xue Bai,Rui He,Lihui Zhang,Zhenfa Liu,Yanji Wang
Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 cathode material was synthesized by a facile one-step solid-state process. The effect of Mg 2+ /F − co-doping on grain morphology, phase structure, and electrochemical properties was studied by a series of characterizations. Scanning-electron-microscopy images show that Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 (denoted LNMO-MF) particles grow larger than pure LiNi 0.5 Mn 1.5 O 4 particles. X-ray diffraction, Raman spectra , Fourier transformation infrared spectroscopy , X-ray photoelectron spectroscopy, and cyclic-voltammetry tests indicate that all samples mainly display a Fd -3m space group and more Mn 3+ ions in the LNMO-MF sample after Mg 2+ /F − co-doping, which is conducive to increasing the cationic disorder degree and enhancing the electronic conductivity of electrode material. Results show that the LNMO-MF cathode material delivers an excellent rate performance with discharge capacities of 142, 144, 140 136, 132, 124, 115, and 100 mAh g −1 at 0.2, 0.5, 1, 2, 3, 5, 7, and 10C (1C = 140 mAh g −1 ), respectively. Remarkably, LNMO-MF also shows cycling stability with a capacity retention of 86.2% at 5C after 400 cycles, which is much higher than that of pure LiNi 0.5 Mn 1.5 O 4 (67.7%). The improvement of LNMO-MF's electrochemical properties could be ascribed to the Mg 2+ /F − co-doping, delivering a more stable structure, better crystallinity , the highest Li + diffusion coefficient , and the lowest charge-transfer resistance.
研究领域:
材料科学
·
电化学
·
无机非金属材料
·
能源存储
·
锂离子电池
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2024
·Vol. 43
·期 3
·543-551
·
IF 5.2
Lang Ruan,Zeyun Zhou,Yi Hu,Ruifeng Peng,Xiaoyan Chen,Ming Cheng,Zhi Zhou,Mao Xia
The technology of solid-state lighting has developed for decades in various industries. Phosphor, as an element part, determines the application domain of lighting products. For instance, blue and red-emitting phosphors are required in the process of plant supplementing light, arrow-band emitting phosphors are applied to backlight displays, etc. In this work, a Bi 3+ -activated blue phosphor was obtained in a symmetrical and compact crystal structure of Gd3SbO7 (GSO). Then, the co-doping strategy of alkali metal ions (Li + , Na + , and K + ) was used to optimize the performance. The result shows that the photoluminescence intensity is increased by 2.1 times and 1.3 times respectively by introducing Li + and K + ions. Not only that, it also achieves narrow-band emitting with the full width of half-maximum (FWHM) reaching 42 nm through Na + doping, and its excitation peak position also shifts from 322 to 375 nm, which can be well excited by near-ultraviolet (NUV) light emitting diode (LED) chips (365 nm). Meanwhile, the electroluminescence spectrum of GSO:0.6 mol%Bi 3+ ,3 wt%Na + matches up to 93.39% of the blue part of the absorption spectrum of chlorophyll a . In summary, the Bi 3+ -activated blue phosphor reported in this work can synchronously meet the requirements of plant light replenishment and field emission displays .
研究领域:
材料科学
·
光学工程
·
固体照明
·
光电子学
·
农业光生物学
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2022
·
IF 3.662
Yuhong Zhang,Nan Zhang,Pengcheng Wang,Xingke Zheng,Yibin Guo,Hang Liu
In this work, tungstate BaWO 4 phosphors doped Ho 3+ -Yb 3+ -Gd 3+ ions are successfully synthesized through solid-state reaction method. Under the excitation of a 980 nm laser, the up-conversion (UC) luminescence properties are investigated simultaneously. The blue (465 nm, 489 nm), green (541 nm) and red (665 nm) emission intensities of BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ samples are dramatically enhanced by 20.59, 9.83, 7.37, and 27.59 times more than those without Gd 3+ ions. The possible reason is discussed, which attributes to the energy transfer efficiency enhancement from Yb 3+ to Ho 3+ due to the lattice expansion induced by Gd 3+ ions. The temperature-sensing properties of BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ samples are also discussed based on the fluorescence intensity ratio (FIR) technology. The sensitivity of temperature measurement for BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ sample is higher than that of BaWO 4 : Ho 3+ /Yb 3+ . It proves that the codoped Gd 3+ ions can also increase the temperature sensitivity because the higher UC emission efficiency will lead to a high signal-to-noise ratio. The result provides an effective way to design UC luminescence materials with high temperature sensing properties.
研究领域:
材料科学
·
光学材料
·
发光学
·
传感器技术
·
无机功能材料
✓ 已验证
DOI
高影响因子
Energy Technology
·
2021
·Vol. 9
·期 12
·2100743
·
IF 3.631
Xin Hou,Penggang Ren,Zhong Dai,Zhengzheng Guo,Zengping Zhang,Aiyue Sun,Wenwei He,Fang Ren,Yanling Jin
Herein, nitrogen, oxygen codoped porous carbon nanofibers (CNFs) from corn residue-derived lignin are fabricated via the electrospinning method, followed by introduction of graphenes (GNs) via a simple “brush-coating and drying” process. The obtained GN-coated carbon nanofibers (CNFs@GNs) exhibit a 3D network architecture, abundance of heteroatoms, excellent electrical conductivity, high specific surface area (700.92 m 2 g −1 ), thus boosting the electrochemical performances. The CNFs@GNs electrode delivers a higher specific capacitance of 271.1 F g −1 than CNFs (200.3 F g −1 ) at 1 A g −1 . Furthermore, the assembled CNFs@GNs symmetric supercapacitor exhibits an energy density of 20.3 Wh kg −1 at the power density of 199.97 W kg −1 together with a high charge/discharge reversibility of 97.3% and Coulombic efficiency of 99.81% after 10 000 cycles. This “brush-coating and drying” strategy utilized here provides a convenient and efficient route for designing CNFs and GN composites and can be utilized in other active materials.
研究领域:
材料科学
·
纳米科技
·
电化学
·
能源存储
·
功能材料
✓ 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
Sustainable Energy & Fuels
·
2019
·Vol. 3
·期 9
·2237-2245
·
IF 4.912
Yulin Chen,Yu Li,Fengnan Yao,Cong Peng,Chen Cao,Yiyu Feng,Wei Feng
Two-dimensional (2D) graphene-based materials are widely applied as electrodes for supercapacitors due to their vast surface area and excellent charge mobility. However, the pursuit of the theoretical capacitance of graphene has lasted besides the improvements of charge/discharge rate and cycling life. In this work, a nitrogen and fluorine co-doped holey graphene hydrogel (NF-HGH) was synthesized by using consecutive solvothermal treatments for creating vacancies on the graphene basal plane and introducing heteroatoms into the graphene framework. The NF-HGH as an electrode for supercapacitors exhibited a remarkable electrochemical performance of 345.4 F g−1 at 1 A g−1 in 6 M KOH electrolyte. In addition, the specific capacitance of the assembled all-solid-state flexible symmetric supercapacitor (SSC) was 67.3 F g−1 at 1 A g−1, with an outstanding long-term cycling stability over 10 000 cycles. The delivered maximum energy and power densities were 7.99 W h kg−1 and 10.08 kW kg−1, respectively. The abundant pyrrolic-N doped at the edge of etched vacancies and the formed semi-ionic C–F bonds around pyrrolic-N were critical for electrochemical developments, which provided a sensational method to construct carbonaceous frameworks for energy storage systems.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2014
·
IF 1.716
J. Yuan,W.C. Wang,D.D. Chen,M.Y. Peng,Q.Y. Zhang,Z.H. Jiang
Enhanced 1.8 μm emission from Tm 3+ by Yb 3+ sensitization and bubbling in tungsten tellurite glasses has been demonstrated under the excitation of a 976 nm laser diode . Radiative properties such as spontaneous emission probabilities, radiative lifetimes and fluorescence branching ratios along with absorption and emission cross sections have been calculated from the absorption spectra . The influences of Yb 3+ concentration, Tm 3+ concentration, and bubbling time on spectroscopic properties have been thoroughly investigated. It is found that with increasing the bubbling time to 35 min, OH − content deceases sharply while 1.8 μm emission intensity improves greatly and 3 F 4 level lifetime prolongs to 1.57 ms close to radiative time. After 35 min, they change very little due to almost reaching the dynamic balance. The strength of interaction between Tm 3+ and OH − is determined. The energy transfer mechanism between Yb 3+ and Tm 3+ is proposed by photoemission spectroscopy and lifetime measurement. The energy transfer coefficients have been analyzed by the extended spectral overlap method and hopping model. Large ratio of the forward energy transfer from Yb 3+ to Tm 3+ to the backward one (223) and high energy transfer efficiency (97%) from Yb 3+ to Tm 3+ ensure efficient 1.8 μm emission. Hence, Yb 3+ sensitization and the reduction of OH − content could be expected to open up a possibility to achieve high efficient 2.0 μm lasing from Tm 3+ under a 976 nm LD pump.
研究领域:
光学材料
·
激光物理
·
固体激光器
·
光谱学
·
无机非金属材料
·
光子学
·
稀土发光材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Zuocheng Luo,Qingfeng Zhang,Wei Xie,Tong Yuan,Qisheng Zang,Ning Wang,Hanxiao Fan,Shuhong Xie,Xiaoping Ouyang
Potassium ion hybrid capacitors (PIHCs) have attracted widespread attention as combining the advantages of potassium ion batteries (PIBs) with supercapacitors . However, the sluggish kinetics caused by the large radius of K + hinder the practical application of PIHCs. Herein, we synthesized a boron and fluorine co-doping interlaced network porous carbon nanofibers (BF-PCNFs), which was used as the freestanding anode of PIHCs the freestanding anode of PIHCs to alleviate large volume expansion and increase conductivity. Benefiting from the B, F co-doping and porous interlace nanostructure of BF-PCNFs, the anode shows 185 mA h g −1 under a load of 12.6 mg cm −2 , a reversible capacity of 176 mA h g −1 at 1000 mA g −1 after 6000 cycles, and the capacity retention from 100 mA g −1 to 5000 mA g −1 is 62%. Furthermore, the PIHCs based on BF-PCNFs as anode and activated carbon as cathode exhibit an energy density of 87 Wh kg −1 and a power density of 393 W kg −1 . The capacity retention is as high as 78% over 4000 cycles. Considering the exceptional rate performance, long cyclability and high-mass-loading, our work may supply a new strategy for designing novel energy storage devices with outstanding performance.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米科技
·
功能材料
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
C. Wang,X.Z. Zheng,L. Yue,P.J. Xia,M. Xu,W.B. Dai
The exploration of stable/efficient phosphor for n -UV chip pumped white light-emitting diodes ( w LEDs) remains an arduous task. Herein, a novel series of color tunable Eu 2+ /Tb 3+ /Sm 3+ tridoped Sc-based cyclosilicate phosphors (KBaScSi 3 O 9 : Eu 2+ /Tb 3+ /Sm 3+ ) have successfully designed and obtained via facile solid-state reaction based on comprehensive consideration of rigidly structural network of host, weak electron-phonon coupling strength and spectral adjustability of codopants via energy transfer (ET). The crystallographic occupancies of Eu, Tb and Sm primary in Ba/K, Ba and Ba sites in the monoclinic host, respectively were determined on the basis of the Rietveld refinements and crystal chemistry rules. The photoluminescence (PL) properties were systematically investigated in conjunction with structural analyses, implying that the ‘warm’ white light with excellent thermal stability is stemmed from combination of optimized blue (Eu 2+ ), green (Tb 3+ ) and red (Sm 3+ ) emissions via Eu → Tb → Sm ET strategy. Interestingly, Tb ions play both roles of green light luminescent center and ET bridge to achieve cascade ET for connecting Eu/Sm ion pairs because of the adverse metal-metal charge transfer (MMCT) effect (Eu 2+ + Sm 3+ → Eu 3+ + Sm 2+ ). Furthermore, the phosphor-converted w LEDs (pc- w LEDs), by encapsulating the optimal KBS: 4 %Eu/4 %Tb/6 %Sm with commercial n -UV LED chip, show high thermal stability with satisfactory electroluminescence (EL) performances. These results indicate the KBS: Eu/Tb/Sm phosphors are potential candidates for application in high power n -UV pumped pc- w LEDs.
研究领域:
材料科学
·
发光材料
·
固态照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）