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
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
DIAMOND AND RELATED MATERIALS
·
2020
·
IF 2.65
Xiao-yu Zhang,Min Xu,Sheng-zhu Cao,Wen-bo Chen,Wen-yao Yang,Qin-yu Yang
Diamond/copper composite has been considered as one of the next generation thermal management materials. Interfacial modification is an essential means of ameliorating interface wettability and bonding of diamond/copper composite for improving its thermal conductivity . In the present work, Diamond/copper composite was manufactured by using spark plasma sintering (SPS) technology with 60% volume fraction of diamond mixed with 40% volume fraction of copper power, chromium powder (0.7 wt%) and scandium oxide powder (0.21 wt%). A series of material analysis methods were used to characterize the microstructure, interfacial layer , phase compositions and distributions of Diamond/copper composite. The total and partial electron density of states (DOS) for Diamond-Cr-Sc 2 O 3 interfacial model was investigated by means of first-principles calculations from CASTEP modules. The results showed Sc 2 O 3 made a 5–20 nm well-arranged and uniformly distributed interfacial chromium carbide layer in the interface region, which played a critical role in increasing the amount of reactive interfacial bonding and decreasing defect. The addition of Sc 2 O 3 brought the increasing number of heat transfer carriers at the interface and made the interface energy system more stable. The obtained diamond/copper composite exhibited that the wettability between diamond particles and copper was effectively improved. The thermal conductivity of diamond/copper is 872 W/(m·K) and the possible reasons for doping rare-earths Sc 2 O 3 to improve the thermal conductivity were discussed.
研究领域:
材料科学
·
复合材料工程
·
界面科学
·
热管理材料
·
粉末冶金
·
计算材料学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Chengyuan Liu,Zhiwei Liu,Qiming Li,Hongkun Niu,Cong Wang,Zhaowen Wang,Bingliang Gao
Aluminum battery offers a new possibility for low cost and large-scale stationary storage of electricity because it can be made with cheap materials and exhibits high theoretical mass specific capacity and power density. Among many cathodic materials, graphite/graphene may be one of the most promising cathode materials for aluminum-ion battery. A suitable three-dimensional structure of the cathode is an important factor for the high performance of battery. In this paper, a binder-free cathode is prepared by dropcasting small ultrasonicated graphite flakes (u-GF) on carbon fiber cloth (CFC) which provides a three-dimensional network skeleton for the new cathode. Al|EMImCl-1.3AlCl 3 |u-GF@CFC battery exhibits a high discharge specific capacity of ~140 mAh g −1 at 100 mA g −1 . The battery has good rate performance and cycling stability: the capacity still exceeds 100 mAh g −1 at 600 mA g −1 with a high coulomb efficiency of 98% and maintains 60 mAh g −1 at 3000 mA g −1 over 300 cycles.
研究领域:
电化学
·
能源材料
·
纳米材料
·
储能技术
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2012
·Vol. 22
·期 43
·22873-22880
·
IF 5.968
Xiwei Zhang,Xiujuan Zhang,Xiaozhen Zhang,Yuping Zhang,Liang Bian,Yiming Wu,Chao Xie,Yuanyuan Han,Yan Wang,Peng Gao,Liu Wang,Jiansheng Jie
The narrow indirect bandgap of Si hinders the full absorption and utilization of the solar light. Energy band engineering to the Si based photovoltaic devices is essential to address this problem. Here we report the fabrication of ZnSe nanoribbon (ZnSeNR)/Si nanowire (SiNW) p–n heterojunction arrays by directly growing or simply drop-casting the p-type ZnSeNRs on highly aligned n-type SiNW arrays. Phosphorus (P) was used as dopant to achieve robust p-type doping in the ZnSe nanostructures with a hole concentration as high as 6.5 × 1018 cm−3. Thanks to the matched bandgap and the light trapping arising from the one-dimensional (1D) array structure, the heterojunction arrays exhibited improved light absorption, particularly in the blue/UV wavelength range. Moreover, by taking advantage of the ohmic contact between graphene and p-ZnSeNR, heterojunction array solar cells with graphene transparent electrode were fabricated, giving rise to a power conversion efficiency of ∼0.78% under AM 1.5G illumination. It was found that the surface passivation to the SiNW array played an important role in determining the device performance; an efficiency up to 2.27% was obtained after surface modification with methyl groups. Our results demonstrate the heterojunction arrays, together with the graphene transparent electrodes, could be promising candidates for high-performance and low-cost photovoltaic applications.
研究领域:
材料科学
·
纳米科技
·
半导体物理
·
光电子学
·
能源材料
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2020
·
IF 6.155
Liqianyun Xu,Liuyang Zhang,Bei Cheng,Jiaguo Yu,Ahmed A. Al-Ghamdi,S. Wageh
Poor conductivity and rate capability are the obstacles faced by nickel-cobalt composites as electrode materials for supercapacitor application. Herein, simple electrochemical treatment conducted by cyclic voltammetry is applied and the overall performance of the active material is considerably enhanced. We discover that this treatment triggers the formation of Ni-Co-Cu ternary composite and optimizes the crystal structure of the untreated counterpart. The areal capacitance of the treated sample rockets up to 6.13 F cm −2 at 2 mA cm −2 , almost 13 times higher than the untreated ones. Besides, the resistance is substantially reduced by cyclic voltammetry treatment. Moreover, the Coulombic efficiency and stability are concurrently elevated. The reasons behind this treatment are mulled over and reasonable hypothesis is suggested. This study provides a cheap and effortless way to reform the structures of as-obtained samples as well as vigorously raise the performance of current available materials.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 26
·46416
·
IF 1.901
Xiang Lin,Kai Zhang,Ke Li,Dongyun Ren
Carbonaceous nanoparticles (CNPs), including carbon black, carbon nanotubes, and graphene nanopiece, were selected as nanoadditives for investigating the rheological behavior dependence of their polymer-based composites on morphological and interfacial structure. Polypropylene (PP) was adopted as matrix and a series of contents of CNPs were used for sample compounding. With identical concentration, the morphological structure of CNPs was emphasized as the dominant effect affecting the shear viscosity and the compressibility of PP/CNPs melts. The viscosity dependence on the CNPs contents and physical structure, such as particle size, aspect ratio, and specific area, was fully discussed in this work. The newly-introduced inner voids, induced around the interface region between matrix and CNPs during physical mixing, were contributive to the rheological deviation, which was further reflected from the melt compressibility. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46416.
研究领域:
高分子科学
·
复合材料学
·
流变学
·
纳米材料科学
·
聚合物加工
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Hui Wang,Houzhen Chen,Hongjiao Wang,Lei Wu,Qixing Wu,Zhongkuan Luo,Fang Wang
The electrochemical performance of the lithium−oxygen (Li−O 2 ) batteries largely depends on the material and architecture of the catalytic cathode. In this paper, to avoid the parasitic reactions of carbon and binder with discharge products and reaction intermediates, we proposed an effective design of a free-standing catalytic cathode for Li−O 2 batteries. The FeCo 2 O 4 @Ni electrode consists of FeCo 2 O 4 nanosheets grown directly on nickel (Ni) foam. The resultant hierarchical macroporous/mesoporous structure provides sufficient space for the insoluble discharge product Li 2 O 2 and catalytically active sites for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Consequently, the carbon- and binder-free self-supporting electrode has demonstrated a high discharge capacity with relatively low charge overvoltage and a better cycle performance than the corresponding carbon-based electrodes.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电催化
·
储能技术
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 48
·32903-32909
·
IF 4.449
Fan Zhang,Jun Song,Ming Chen,Junchen Liu,Yuying Hao,Yuncai Wang,Junle Qu,Pengju Zeng
Organic–inorganic metal halide perovskites have led to remarkable advancements in emerging photovoltaics. The rapid increase in the power conversion efficiency (PCE) of PSCs has been mainly achieved by improving perovskite morphology and crystallinity. Herein, we report a simple and effective means to improve perovskite grain sizes using a porous hole transport layer (i.e., PEDOT:PSS in this work). We used polystyrene nanospheres as a sacrificial template to fabricate the porous-PEDOT:PSS. The growth of the CH3NH3PbI3 perovskite film on the porous-PEDOT:PSS substrate yields a dramatic improvement in crystallinity and an enhancement in perovskite grain sizes. When the porous structure was applied as a hole transport layer in PSCs with planar heterojunction structures, the efficiency was significantly enhanced from 15.33% for the planar device to 17.32%. This simple method for enhancing perovskite morphology and crystallinity paves the way for its application to other device architectures for enhanced photovoltaic performance.
研究领域:
材料科学
·
光伏技术
·
纳米结构调控
·
能源材料
·
薄膜制备
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 17
·9362-9367
·
IF 3.43
Weifeng Huang,Yingcai Zhu,Yong Liu,Lijuan Liu,Changchun Yang,Wei Xu
The quaternary chalcogenides consisting of earth-abundant elements such as Cu2ZnSnSe4 (CZTSe) have promising electrical and optical properties prompting enormous technological interest. Understanding different types of defects including Cu/Zn ordering is believed to be the key point to tackle technological challenges such as a large open circuit voltage deficit in CZTSe. The Te doped Cu2.2Zn0.8SnSe4−xTex (x = 0.01–0.04) were investigated using X-ray absorption fine structure spectroscopy at the Cu, Zn, and Se K-edges as well as at the Te L3-edge. Cu at the zinc site with anti-site defects and oxygen interstitials are identified. The detailed electronic structure upon Te doping is studied, providing insights into the rich defect chemistry present in this compound.
研究领域:
材料科学
·
凝聚态物理
·
无机化学
·
半导体材料
·
光电功能材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Xi-Ming Song,Xin Zhou,Chunxue Yuan,Yu Zhang,Qiang Tong,Ying Li,Luxia Cui,Daliang Liu,Wei Zhang
We reported a novel Fe 2 O 3 /rutile TiO 2 nanorod (NR) arrays with the heterogeneous structure for photoelectrochemical (PEC) cells, which were fabricated on fluorine-doped tin oxide glass (FTO) substrates that serve as model architecture via a hydrothermal method. Fe 2 O 3 was revealed as an inexpensive and eco-friendly semiconductor sensitizer to make TiO 2 respond to visible light . By using this photoanode, the photoelectric conversion and water splitting properties of PEC cells based on the one-dimensional (1D) Fe 2 O 3 /TiO 2 heterostructures were investigated in detail under simulated sunlight. Meanwhile, the optimization of photovoltaic performance was also achieved by regulating the amount of Fe 2 O 3 . The open circuit voltage and short circuit current of the Fe 2 O 3 /TiO 2 solar cell can reach 0.435 V and 1.840 mA/cm 2 , respectively. In addition, theoretical analysis of the photoelectric effect is preliminarily explored on the basis of the flat band potential results.
研究领域:
材料科学
·
物理化学
·
能源科学
·
纳米科技
·
光催化
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 33
·14103-14107
·
IF 3.288
Chanchan Xu,Le Lv,Dawei Luo,Wei Liu
By using pyrazine derivatives, three different types of copper(I) iodide based inorganic–organic hybrid structures, 1D-CuI(2-mo-pz) (1, 2-mo-pz = 2-methoxy-pyrazine), 2D-CuI(2,3-dm-pz)0.5 (2, 2,3-dm-pz = 2,3-dimethyl-pyrazine), and 2D-Cu2I2(2,5-dm-pz)2 (3, 2,5-dm-pz = 2,5-dimethyl-pyrazine), have been obtained by using a slow-diffusion method. Single crystal and powder X-ray diffraction analyses reveal that these hybrid structures are a one-dimensional (1D) staircase chain based structure, two-dimensional (2D) staircase-chain based structure, and 2D rhomboid dimer based structure, respectively. All of the three compounds show photoluminescence, with the internal quantum yield (IQY) as high as 88.2% for 1. This work provides evidence that for this type of hybrid materials, the structure of the inorganic module could be determined by the selection of the organic ligands and that the substituted group on the organic ligands can influence the luminescence efficiency of the hybrid structures.
研究领域:
无机化学
·
材料化学
·
配位化学
·
光物理
·
功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）