JOURNAL OF ALLOYS AND COMPOUNDS
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2023
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IF 6.2
Yongfeng Bu,Hongyu Zhang,Jinzhi Hu,Wenya Jiang,Qin Kang,Shihao Wang,Yuman Li,Shengda Tang,Hongyu Liang
Metallic selenides are considered as a promising class of alternative anodes for sodium ion batteries due to the high capacity conferred by their hybrid sodium storage mechanism. However, the low reversible volume expansion induced by larger size sodium ion storage greatly limits their cycle life, theoretical capacity mining and electrode thickness enhancement. Herein, a germanium selenide/carbon nanofibers (GeSe/CNFs) sodium storage anode is first reported by taking advantage of the encapsulation and dispersion of electrostatic spinning technology, i.e., GeO 2 is first mixed with polyacrylonitrile and electrospun to form a wrapped structure, followed by in situ pre-oxidation, carbonization, and selenization. For the optimized electrode, it delivers a high capacity up to 567 mAh g −1 based on the mass of GeSe (320 mAh g −1 based on GeSe/CNFs), reaching > 80% of its theoretical capacity, with a > 2300 cycles cycling stability at 1.0 A g −1 . In addition, its capacity barely decays after 700 cycles at near commercial electrode thickness (115 µm, the capacity retention > 47–63% even at the ultrahigh thickness of 187–219 µm). This study opens up new possibilities for the development of Se-based sodium storage anode materials with long life, high capacity and ultra-thick electrode that are expected to meet practical needs.
研究领域:
材料科学
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能源存储
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
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IF 6.2
Qiduo Chen,Shan Tang,Dong Feng,Yuhui Xie,Feng Wu,Delong Xie,Yi Mei,Tianbiao Zeng
As a typical conversion alloyed anode material , Germanium selenide (GeSe 2 ) exhibits isotropic lithiation behavior and high theoretical charge-discharge specific capacity. However, pure GeSe 2 anode faces significant volume expansion (∼250 %−360 %) and further exploration is needed in the preparation of flexible electrode materials and structural design. Herein, a simple strategy is designed to load GeSe 2 /C-2 nanoparticles with porous carbon-coated structure on a flexible cross-networking substrate. The 3D network substrate is composed of highly conductive carbon nanotubes and adhesive cotton cellulose fibers. A two-step method involving coating and cross-linking is designed to achieve the fabrication of self-supporting flexible electrodes. As an anode for LIBs , the one layer GeSe 2 discs with ∼0.65 mm thickness manifest capacities of 827.1, 744.4, 676.3, and 472.9 mAh g −1 at 0.1, 0.2, 0.5, and 1 A g −1 , respectively. This superior Li + storage performance can be attributed to the positive collective impact from the integration of nano-scale material, low crystalline properties, and carbon sponge skeleton. Furthermore, the GITT tests indicate that the diffusion coefficient of Li + in the GeSe 2 -based electrodes ranged from 10 −15 to 10 −12 cm 2 /s, and the thickness of the flexible electrode (including two layers) has a negligible impact on its electrochemical performance.
研究领域:
材料科学
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能源存储
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DOI
高影响因子
Journal of Energy Chemistry
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2019
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IF 5.162
Mingtao Yan,Huiyuan Geng,Peng Jiang,Xinhe Bao
Thermoelectric properties of orthorhombic or rhombohedral GeSe have attracted great attention recently, with the rise of its structural analog SnSe. However, the p -type cubic GeSe with higher symmetry and higher valence band degeneracy, which might exhibit higher thermoelectric performance, has never been synthesized. Here we report on the successful synthesis of p -type crystalline cubic GeSe by alloying with Sb 2 Te 3 and the spontaneously formed Ge-vacancies. An unexpected glass-like temperature independent lattice thermal conductivity is observed in crystalline cubic GeSe, which results from strong phonon scattering by vacancy-induced disorders. Combining the multiple scattering theory and chemical bond analysis, we further reveal the existence of Anderson localization induced by Ge-vacancies. The Anderson localization results in a nearly constant Seebeck coefficient with increasing the carrier concentration. These results provide a general insight towards understanding and improving the thermoelectric properties of thermoelectric materials with vacancies and atomic-scale disorders.
研究领域:
材料科学
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凝聚态物理
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
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IF 6.3
Jing Zhou,Li Gao,ShengWen Yang,Zhenming Qu,Yu Cao,Jinbo Pang,Jian Ni,Jianjun Zhang
Germanous selenide (GeSe) is an emerging photoactive layer material due to its excellent photoelectric properties, low cost and environmental friendliness. However, severe carrier recombination in the GeSe photoactive layer remains a significant factor limiting the conversion efficiency of GeSe solar cells. In this study, the GeSe photoactive layers were doped copper chloride (CuCl 2 ) solution, enabling the distribution of Cu 2+ ions throughout the layer, primarily accumulating on the GeSe grain surface. Its impact on the carrier transport in the GeSe photoactive layer was studied by ultraviolet photoelectron spectroscopy, kelvin probe force microscopy, and transient photovoltage. The doping can not only increase the Fermi level of the GeSe, but also adjust the local built-in potential on grain boundaries, so that the charge carriers can be redistributed in the three-dimensional space. Notably, at the grain boundaries, the hole flow before doping changes to electron flow, effectively reduces the recombination probability of charge carriers, and increases the carrier lifetime from 200.23 to 374.57 μs. As a result, the conversion efficiency after processing with CuCl 2 is increased from 1.98 % to 3.01 %. This study provides a reference for understanding the carrier kinetics in GeSe solar cells to improve the photoelectric conversion performance of the device.
研究领域:
材料科学
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光伏技术
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半导体物理
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DOI
高影响因子
INSTRUMENTATION SCIENCE & TECHNOLOGY
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2022
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IF 1.509
Ze-Ying Hao,Yao Liu,Zhou-Hao Zhao,Qi Wang
Although surface plasmon resonance (SPR) methods are frequently employed due to their remarkable advantages such as reduced sample requirements, they confront a significant challenge in terms of sensitivity improvement. GeSe is an appropriate material for resolving this issue. According to the theoretical basis of the research, GeSe is a two-dimensional material which is a direct band gap semiconductor that may be utilized to promote electron transport and stimulate greater SPR phenomena. The first use of GeSe in an optical fiber sensor is reported in this study. A U-shaped optical fiber-GeSe-Au sensor is proposed. As a two-dimensional material with comparable physical characteristics to GeSe, MoS2 is compared to GeSe to characterize its influence upon the sensitivity. The sensitivity of fiber-GeSe-Au sensor is 7398.1 nm/refractive index unit (RIU), which is nearly twice as sensitive as a gold film SPR sensor and 1.5 times as sensitive as a sensor utilizing MoS2 nanosheets with the same structure. This study introduces a novel approach for enhancing the sensitivity, which gives a new option for monitoring biological substances at low concentrations with high sensitivity and stability and demonstrates that GeSe nanosheets have significant promise for future applications.
研究领域:
材料科学
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光学工程
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生物传感
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DOI
高影响因子
Science China-Chemistry
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2023
·Vol. 66
·期 4
·1086-1093
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IF 9.6
Wang Linan,Tu Chenchen,Gao Hongbo,Zhou Jiazheng,Wang Hongshan,Yang Zhihua,Pan Shilie,Li Junjie
Infrared (IR) birefringent materials with large optical anisotropy and wide transparency range are important for efficient light manipulation in various IR optical devices. Herein, two new IR birefringent materials AMgGeSe 3 (A = Li, Na) with large optical anisotropy were rationally designed by a rigid octahedron and flexible dimer combined strategy and fabricated in experiment. The introduction of rigid [LiSe 6 ]/[NaSe 6 ] and [MgSe 6 ] octahedra effectively regulates the geometry and arrangement of the flexible [Ge 2 Se 6 ] dimers, resulting in the birefringence as large as 0.334@1,064 nm in LiMgGeSe 3 and 0.445@1,064 nm (the largest one in the reported [Ge 2 Se 6 ] dimer-contained selenides) in NaMgGeSe 3 . Density functional theory (DFT) calculations and statistical analyses highlight the influence of polarizability anisotropy, density, arrangement of units, as well as layer distance on birefringence. The results indicate that AMgGeSe 3 (A = Li, Na) crystals are the promising IR birefringent materials and it gives an insight into the exploration of new IR birefringent materials with large birefringence based on the clamping effect from rigid groups.
研究领域:
材料科学
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光学
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DOI
高影响因子
CHEMISTRY OF MATERIALS
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2017
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IF 9.466
Bin-Wen Liu,Min-Yi Zhang,Xiao-Ming Jiang,Shu-Fang Li,Hui-Yi Zeng,Guo-Qiang Wang,Yu-Hang Fan,Yong-Fei Su,Chunsen Li,Guo-Cong Guo,Jin-Shun Huang
Two new polar polyselenides Rb4Ge4Se12 (1) and Cs4Ge4Se12 (2) with rarely reported dimeric [Ge2Se4(μ-Se2)]4– units were synthesized. They present large second-harmonic generation (SHG) intensities of 7.5 and 6.5 times that of the benchmark AgGaS2 with type I phase-matching behavior, high laser-induced damaged thresholds, a wide transmission region and congruently melting behavior, making them excellent candidates for IR nonlinear optical (NLO) applications. The SHG functional motifs of both compounds are determined to be [Ge2Se4(μ-Se2)]4– unit by time-dependent density functional theory calculation, which further reveals that charge transfers from the lone pairs of terminal Se atoms to the five σ* orbitals of five-membered ring Ge2Se3 have a predominant contribution to the total SHG effect.
研究领域:
材料科学
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光学
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DOI
高影响因子
Science Bulletin
·
2023
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IF 18.9
Ziqi Zhou,Tao Shen,Pan Wang,Quanlin Guo,Qinghe Wang,Chenjun Ma,Kaiyao Xin,Kai Zhao,Yali Yu,Biao Qin,Yue-Yang Liu,Juehan Yang,Hao Hong,Kaihui Liu,Can Liu,Hui-Xiong Deng,Zhongming Wei
Polarization-sensitive photodetectors, with the ability of identifying the texture-, stress-, and roughness-induced light polarization state variation, displace unique advantages in the fields of national security, medical diagnosis, and aerospace. The utilization of in-plane anisotropic two-dimensional (2D) materials has led the polarization photodetector into a polarizer-free regime, and facilitated the miniaturization of optoelectronic device integration. However, the insufficient polarization ratio (usually less than 10) restricts the detection resolution of polarized signals. Here, we designed a sub-wavelength array (SWA) structure of 2D germanium selenium (GeSe) to further improve its anisotropic sensitivity, which boosts the polarized photocurrent ratio from 1.6 to 18. This enhancement comes from the combination of nano-scale arrays with atomic-scale lattice arrangement at the low-symmetric direction, while the polarization-sensitive photoresponse along the high-symmetric direction is strongly suppressed due to the SWA-caused depolarization effect. Our mechanism study revealed that the SWA can improve the asymmetry of charge distribution, attenuate the matrix element in zigzag direction, and the localized surface plasma, which elevates the photo absorption and photoelectric transition probability along the armchair direction, therefore accounts for the enhanced polarization sensitivity. In addition, the photodetector based on GeSe SWA exhibited a broad power range of 40 dB at a near-infrared wavelength of 808 nm and the ability of weak-light detection under 0.1 LUX of white light (two orders of magnitude smaller than pristine 2D GeSe). This work provides a feasible guideline to improve the polarization sensitivity of 2D materials , and will greatly benefit the development of polarized imaging sensors.
研究领域:
光电子学
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纳米光子学
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偏振成像
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二维材料
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光电探测器
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半导体器件
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DOI
高影响因子
危险品化学品经营许可证（带存储）