JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Siqi Wang,Zhi Yang,Yuejun Sun,Yu Xiao,Li-Dong Zhao
PbTe-based thermoelectric materials are considered to be a medium-temperature thermoelectric candidates and the high-performance n -type PbTe is urgently to be developed to match its p -type counterpart on account of practical application. Herein, we firstly optimized the carrier density of n -type PbTe through Sb doping, and obtained a maximum ZT value of ∼1.0. Then, based on the optimized carrier density, we introduced ternary compounds AgSb(Se, Te) 2 to suppress the lattice thermal conductivity . Minimum lattice thermal conductivity of n -type PbTe was reduced as low as ∼0.53 W m −1 K −1 and ∼0.62 Wm −1 K −1 through introducing AgSbSe 2 and AgSbTe 2 , respectively. Combining the maintained electrical properties with suppressed thermal conductivity , maximum ZT values ∼1.2 and ∼1.3 were obtained in PbTe+2%AgSbSe 2 and PbTe+2%AgSbTe 2 , respectively. This work provides an effective strategy of synergistically balancing charge and phonon transports in n -type PbTe with ternary AgSb(Se, Te) 2 compounds.
研究领域:
材料科学
·
热电转换
·
凝聚态物理
·
半导体物理
·
功能材料
·
能量转换材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2016
·
IF 2.822
Xinhe Zhang,Bo Jin,Linlin Li,Tuo Cheng,Huanhuan Wang,Peiming Xin,Xingyou Lang,Chuncheng Yang,Wang Gao,Yongfu Zhu,Qing Jiang
Non-graphitizable carbon (NGC) has been obtained by carbonizing tubular polypyrrole (T-PPy) synthesized through a self-degraded template method . K-NGC/S composite has been prepared by mixing S with K-NGC via melt-diffusion method where NGC has been activated by potassium hydroxide (denoted as K-NGC) and is used as a conductive additive. The as-prepared K-NGC/S composite shows good specific discharge capacity and rate capability with an initial specific discharge capacity of 1121.9 mAh g − 1 and a specific discharge capacity of 729.7 mAh g − 1 after 50 cycles at a current density of 335 mA g − 1 , which is better than pure S. This improvement in the specific discharge capacity and the rate capability of the cell with K-NGC/S composite as a cathode material is realized by the existence of K-NGC, which can offers a superb conductive environment for S, effectively encapsulate S, restrain the outward diffusion of polysulfides , buffer volume change upon cycling and reduce the dissolution of lithium polysulfides into the electrolyte. The good electrochemical performance of K-NGC/S composite would make it become a promising cathode material for lithium-sulfur batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2018
·Vol. 61
·期 9
·1209-1217
·
IF 4.318
Sun Fu-Hua,Dong Jinfeng,Dey Shaugath,Asfandiyar,Wu Chao-Feng,Pan Yu,Tang Huaichao,Li Jing-Feng
Cu 12 Sb 4 S 13 tetrahedrite has received great attention as an earth-abundant and environmental-friendly thermoelectric material. This work aims to uncover the thermoelectric performance-enhancing effect and the mechanism of nickel doping on tetrahedrite. A series of Cu 12− x Ni x Sb 4 S 13− δ ( x = 0.5, 0.7, 1.0, 1.5 and 2.0) compounds were synthesized by mechanical alloying combined with spark plasma sintering. It is found that the thermal conductivity sharply reduces with increasing Ni content over the entire temperature range, < 0.9 W m −1 K −1 , accompanied with an enhanced thermoelectric power factor. The model predicted that the reduced lattice thermal conductivity is attributed to mid-frequency phonon scattering, caused by precipitates and dislocations resulting from Ni doping. Consequently, a high ZT value up to 0.95 at 723 K was achieved for Cu 11 NiSb 4 S 13− δ , corresponding to a ∼46% increase over non-doped Cu 12 Sb 4 S 13− δ . Furthermore, the cyclic measurement showed that the Ni-doped tetrahedrites displayed high chemical stability.
研究领域:
材料科学
·
热电材料
·
无机化学
·
固体物理
·
能源材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 49
·期 11
·18776-18785
·
IF 5.2
Jiaxu Cheng,Siwei Jiang,Jiahong Fan,Jun Yao,Ning Du,Xue Li,Ding Wang,Peng Dong,Zhongren Zhou,Yingjie Zhang
Molten salt electrolytic synthesis of silicon is identified as a potential industry method due to its thorough deoxidization of oxide and short-flow synthetic progress. However, figuring out a more efficient and sustainable strategy for the increase of the reduction process as well as the control of product morphology still needs endless research. In this study, benefiting from the high electrical conductivity of metallic silver and the easy separation of silver from silver-silicon alloys during the electrolysis of SiO 2 , metallic silver was introduced to electric-catalyze the production of silicon. Firstly, metallic silver was introduced into the silica matrix by a simple silver mirror reaction. Secondly, the mixed Ag\SiO 2 precursor was located at the cathode for molten salt electrolysis . Finally, silicon nanowires were herein achieved in molten NaCl–CaCl 2 . Mechanisms of metal Ag played during the electric-polarization process of silica and the electrochemical nucleation of silicon were further analyzed by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Field-Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectra . The results demonstrate that Ag helps construct Si nanowires via a classic Ag-Si binary alloy-droplet process and provided quantitative guidance for the large-yield production of silicon nanowires via adding 0.08–0.17 g Ag versus 1 g SiO 2 , controlling the temperature at 850–900 °C and electrolysis voltage at 2.6–2.8 V (2.6V at first 1 h and 2.8V at last 5 h). The synthesized silicon nanowires present two types of linear structures based on two three-phase interlines (3PIs) models and a streamed long-straight nanowire is observed.
研究领域:
材料科学
·
纳米科技
·
电化学
·
无机化学
·
能源材料
·
半导体材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2014
·Vol. 40
·期 9
·15199-15206
·
IF 2.086
Yanbo Yang,Xiao Peng,Si Chen,Liping Lin,Bao Zhang,Yaqing Feng
The novel hierarchical compact layer involving ZnO and TiO 2 blocking films is used to improve the overall performance of dye-sensitized solar cells. The ZnO compact films are fabricated as a bottom layer to block the electrons injection to the conductive glass and improve the open-circuit voltage. The TiO 2 compact layer is employed to suppress back electron transfer and avoid ZnO contacting the acid dyes directly. The short-circuit current density of the DSSC containing the hierarchical compact layer is improved by 30% compared to that of one with only ZnO as the compact layer. The open-circuit voltage is increased by 4% after introducing the additional TiO 2 blocking layer between the ZnO compact layer and mesoporous TiO 2 layer. Overall, the short-circuit current density, open-circuit voltage and solar energy conversion efficiency are enhanced by 15.3%, 3.7% and 29.6%, respectively, relative to the traditional DSSC without any blocking layers. The ZnO–TiO 2 blocking layer has been characterized by electrochemical impedance spectroscopy , open-circuit voltage decay and dark current measurement to reveal the mechanism of short-circuit current density and open-circuit voltage improvement.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
光伏技术
·
表面科学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2018
·Vol. 38
·期 12
·2132-2140
·
IF 3.525
Lingfeng Li,Xiaolong Zhao,Donglai Pan,Guisheng Li
Photoactive WO 3 is attractive as a photocatalyst for green energy evolution through water splitting. In the present work, an electrochemical anodic oxidation method was used to fabricate a photo-responsive nanotube array-like WO 3 /W (NA-WO 3 /W) photoanode from W foil as a precursor. Compared with a reference commercial WO 3 /W electrode, the NA-WO 3 /W photoanode exhibited enhanced and stable photoelectrocatalytic (PEC) activity for visible-light-driven water splitting with a typical H 2 /O 2 stoichiometric ratio of 2:1 and quantum efficiency of approximately 5.23% under visible-light irradiation from a light-emitting diode ( λ = 420 nm, 15 mW/cm 2 ). The greatly enhanced PEC performance of the NA-WO 3 /Wphotoanode was attributed to its fast electron–hole separation rate, which resulted from the one-dimensional nanotube array-like structure, high crystallinity of monoclinic WO 3 , and strong interaction between WO 3 and W foil. This work paves the way to a facile route to prepare highly active photoelectrodes for solar light transfer to chemical energy .
研究领域:
材料科学
·
物理化学
·
能源化学
·
纳米科技
·
光催化
·
电化学
·
可再生能源
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 8
·10917-10924
·
IF 3.83
Li Yang,Qiushi Dai,Lei Liu,Dingsheng Shao,Kaili Luo,Sidra Jamil,Hong Liu,Zhigao Luo,Baobao Chang,Xianyou Wang
Solid electrolytes could address the increasingly urgent safety and energy density concerns of lithium-ion batteries. Among several kinds of solid electrolytes, Ta-doped Li 7 La 3 Zr 2 O 12 (Ta-LLZO) became a research hotspot because of its high Li-ion conductivity and chemical stability against Li-metal and air. However, the preparation of high quality LLZO ceramic electrolyte via conventional air ambient sintering method is still a big challenge due to the serious “Li-loss” and abnormal grain growth phenomenon during the long-time high-temperature sintering process . Herein, a new rapid ultra-high-temperature air ambient sintering method without mother powder (MP) is put forward for the preparation of high quality Ta-LLZO ceramic electrolyte. The rapid sintering strategy can effectively restrain “Li-loss”. Furthermore, it is demonstrated that the none-mother-powder method is superior to traditional mother-powder method. Ta-LLZO ceramics sintered without MP via this rapid sintering method own small grain size, tight grain boundary, dense microstructure and high conductivity. Specifically, the Ta-LLZO ceramic sintered at 1360 °C for 10 min without MP exhibits high conductivity (8.5 × 10 −4 S cm −1 at 25 °C) and high relative density (97%), which equate those made by hot pressing sintering method. Without MP, the sintering process can avoid a lot of material waste and simplify the operation process. Moreover, the rapid sintering process can sharply shorten sintering time and reduce energy consumption. Therefore, this low-cost high-efficient sintering strategy can be effectively used in the large-scale production of high-quality Ta-LLZO ceramic electrolyte.
研究领域:
材料科学
·
固态离子学
·
能源材料
·
电化学
·
无机非金属材料
·
电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Liying Xian,Min Li,Daping Qiu,Chuang Qiu,Cheng Yue,Feng Wang,Ru Yang
Layered P-type structures are integral to most competitive cathodes for sodium-ion batteries (SIBs). However, the performance of P2-type cobalt-based layered materials is unsatisfactory owing to a low initial discharge capacity caused by Na deficiency. Here, Mn-doped Na x CoO 2 with a P3 structure is synthesized by using a modified solvent-thermal method with calcination . A structural analysis shows that partial Mn doping can effectively control P3 phase formation and increase d -layer spacing, thereby improving the diffusion of Na + . In addition, enhanced electrochemical performance is observed in optimized P3-type Na 0.26 Co 0.48 Mn 0.52 O 2 (NCMO-1), which exhibits a reversible specific capacity of 64 mAh g −1 at 3 A g −1 and a good capacity retention of 58% after 500 cycles. Furthermore, the Na-ion full cell constructed with an NCMO-1 cathode and a hard carbon anode yields a competitive energy density of 175.9 Wh kg −1 at 0.4 A g −1 with excellent cycle stability. Thus, this work provides a new viewpoint on the development of P3 structural materials with higher electrochemical performance for SIBs.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2023
·Vol. 27
·期 5
·1165-1175
·
IF 2.5
Liu Shuling,Zhang Wei,An Yiming,Li Ying,Wang Jie,Wang Chao
The Si-based flexible electrodes attracted increasing research interests owing to the growing demand for high-performance flexible energy storage devices. Herein, a facile and smart self-assembly strategy is adopted to address huge volume expansion and particle aggregation issues of Si-based anodes, and a high-performance freestanding film anode (NC@Si/CNTs/N-rGO) is synthesized. The 3D-crosslinked porous graphene-CNTs networks offer abundant electric conductive pathways, high active sites, large internal space to accommodate the expansion of Si NPs, and facilitate Li + diffusion and insertion/extraction kinetics. The synergistic effect between the well-dispersed Si/NC nanoparticles and 3D porous networks significantly enhances electrochemical performance of Si NPs. The as-prepared NC@Si/CNTs/N-rGO electrode exhibits a high reversible specific capacity of 1089 mAh·g −1 at a charge–discharge current density of 1 A·g −1 after 500 cycles. Even at 2 A·g −1 , the electrode still exhibits an excellent reversible specific capacity of 606 mAh·g −1 after 300 cycles. These indicate that the NC@Si/CNTs/N-rGO is a promising candidate for high-performance flexible anode material in lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
先进电池技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 38
·23415-23421
·
IF 3.108
Sheng Yuan,Ming-Jian Zhang,Xiaoyang Yang,Zongwei Mei,Yongji Chen,Feng Pan
MoS2, a representative two-dimensional transition metal dichalcogenide, gains significant interest due to its unique layered structure and electronic structure. In this work, a novel MoS2-based hybrid thin film was constructed by disordered stacking of MoS2–NMP hybrid particles, which were mainly composed of MoS2(NMP)3 molecules stacking in a nearly-parallel manner through S⋯H–C hydrogen bonds. Interestingly, it presents a higher work function (5.42 eV) than Au (5.32 eV), and a unique thickness-dependent conductivity with p-type semiconductor characteristic. Using it as the back contact of CdTe solar cells, the efficiency was improved by 2.6% compared to the traditional cells, mainly from the great improvement in short-circuit current density (Jsc). This significant improvement in solar performance was ascribed to the matchable energy levels at the CdTe/MoS2-based thin film interface and its unique thickness-dependent conductivity. This work opens a new direction for the extensive applications of TMD-based materials.
研究领域:
材料科学
·
光伏技术
·
纳米材料
·
半导体物理
·
表面科学
·
能源材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 43
·期 17
·15551-15555
·
IF 2.986
Youzhi Wang,Xue Guo,Yurun Feng,Xiao Lin,Hongyu Gong
Ferreous polymer-derived SiCN ceramics (PDCs-SiCN(Fe)) were successfully synthesized by precursor conversion method. The phase composition and microstructure of the obtained products were investigated by XRD , SEM and TEM . The result indicated a mainly amorphous structure with a few α-Fe,and graphite phases in the gaps. The conductivity, electromagnetic parameters and wave absorbing properties of the prepared ceramics were studied at the frequency band from 2 to 18 GHz. The reflectance of PDCs-SiCN(Fe) was about −10 dB (> 90% absorption) in the range of 4–16 GHz with 25 wt% nano-Fe 2 O 3 addition at the thickness 8 mm. The maximum value of dielectric and magnetic loss angle tangent was about 1.5, indicating PDCs-SiCN(Fe) ceramics possessed good absorption performance .
研究领域:
材料科学
·
陶瓷学
·
电磁学
·
功能材料
·
复合材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Siwei Zhao,Ying Chen,Zhiyang Zhao,Longfei Jiang,Chi Zhang,Jianshou Kong,Xufei Zhu
Anodic TiO 2 nanotubes have been intensively studied for the application in supercapacitors , but the formation of nanograss is often avoided for the belief that it may retard capacitive performance. We fabricate TiO 2 nanotubes topped with nanograss by H 3 PO 4 solution soaking and hydrogenation doping, which in fact increases the capacitance of nanotubes in a fast and convenient way. The new structure exhibits an enhanced areal capacitance by up to 67.7% and by up to 23.5% after 2000 times of cycling. The capacitance generally increases with the nanotube length and reaches the maximum with an optimal nanograss length. The electric charge during hydrogenation doping is determined to quantify the general doping effect. Compared with ordinary nanotubes, nanograss has larger contact area with electrolyte during doping. Therefore, the grass-topped structure yields more electric charge and Ti 3+ during doping, which attributes to the improved capacitance.
研究领域:
材料科学
·
纳米技术
·
电化学
·
能源存储
·
表面工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）