Physica E-low-dimensional Systems & Nanostructures最新文献_第2页

Overall water splitting of type-I vdW heterojunction ZnS/Ga2SSe I 型 vdW 异质结 ZnS/Ga2SSe 的整体水分离效果

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-16 DOI: 10.1016/j.physe.2024.116130

Taiyu Hao , Qingyi Feng , Biyi Wang , Zhiwei Li , Bo Li , Hongxiang Deng

In the domain of photocatalysis, type I heterojunctions have received limited attention, and the quest for effective type I photocatalysts persists. This study introduces a novel type I heterostructure, ZnS/Ga₂SSe, and gives a systematic investigation of its electronic properties, optical properties, and photocatalytic performance by DFT calculations. Electronic properties show that ZnS/Ga₂SSe system has a type I band alignment with a 2.26 eV band gap. Different from traditional type I heterostructure, ZnS/Ga₂SSe has an obvious interfacial electric field and a potential barrier, which promotes spatial charge separation and addresses the drawback of easy recombination of photo-generated carriers in traditional type I heterojunctions. The calculated results of Gibbs free energy show that under the 3.3 eV external potential and pH = 14, water splitting reaction can be achieved spontaneously. Moreover, the heterojunction shows good optical absorption in visible regions and 22.28 % STH efficiency which is higher than the reported type I photocatalysts. The biaxial strain can modulate the electronic structure and maintain type I alignment. Tensile can reduce the bandgap and enhance optical absorption, while compression is the opposite. Under 4 % tensile, STH efficiency can reach 40.3 %, while −4 % compression it will decrease to 10.3 %. These conclusions underline the potential of the ZnS/Ga₂SSe heterojunction as a promising photocatalytic material candidate for water splitting and type I heterojunctions is worth exploring as photocatalysis.

在光催化领域，I型异质结受到的关注有限，人们一直在寻求有效的I型光催化剂。本研究介绍了一种新型 I 型异质结构 ZnS/Ga2SSe，并通过 DFT 计算对其电子特性、光学特性和光催化性能进行了系统研究。电子特性表明，ZnS/Ga2SSe 系统具有 2.26 eV 带隙的 I 型带排列。与传统的 I 型异质结构不同，ZnS/Ga2SSe 具有明显的界面电场和势垒，能促进空间电荷分离，解决了传统 I 型异质结中光生载流子易重组的缺点。吉布斯自由能的计算结果表明，在 3.3 eV 的外部电势和 pH = 14 的条件下，可以自发地实现水分裂反应。此外，该异质结在可见光区域具有良好的光吸收性能，STH 效率为 22.28%，高于已报道的 I 型光催化剂。双轴应变可以调节电子结构并保持 I 型排列。拉伸能减小带隙并增强光吸收，而压缩则相反。拉伸 4% 时，STH 效率可达 40.3%，而压缩 -4% 时则降至 10.3%。这些结论强调了 ZnS/Ga2SSe 异质结作为一种有前途的光催化材料用于水分离的潜力，而 I 型异质结作为光催化材料也值得探索。

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引用次数: 0

The key role of anti-solvent temperature in quantum dot/perovskite core-shell nanowire array solar cells 量子点/过氧化物核壳纳米线阵列太阳能电池中反溶剂温度的关键作用

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-12 DOI: 10.1016/j.physe.2024.116131

Yin Ren , Lin He , Yunfei He , Yahong Wang , Sisi Li , Luming Zhou , Peng Ye , Rongli Gao , Gang Chen , Wei Cai , Chunlin Fu

Combining perovskite with infrared quantum dots to construct a core-shell nanostructure nanowire array solar cell can increase the light absorption range and enhance the light absorption and carrier transport efficiency of the solar cell. However, the preparation of a perovskite absorber layer on a nanowire array with quantum dots often presents issues such as high roughness and a large number of lattice defects, which have a negative impact on the photovoltaic performance. The anti-solvent method is a commonly used technique to improve the quality of perovskite. The temperature variation of the anti-solvent can change solubility, and influence the reaction rate and crystal formation process of perovskite, thus affecting its photovoltaic performance. In this study, the quality of perovskite in the core-shell nanostructure nanowire array was improved by controlling the temperature of the anti-solvent (toluene). Experimental results show that as the temperature of toluene increases, the photovoltaic performance is gradually improved. When the toluene temperature was maintained at 75 °C, the device exhibited significantly improved photovoltaic performance with an efficiency of 12.64 %, surpassing the efficiency obtained without any anti-solvent modification. As the temperature of the anti-solvent increases, the absorption of visible and near-infrared light spectrum by the nanowire arrays is enhanced, which promotes the efficient generation of photo-generated carriers. Furthermore, defects in the nanowire arrays gradually decrease, leading to a reduction in carrier recombination. These findings provide valuable insights for advancing core-shell nanostructure nanowire array solar cells.

将透辉石与红外量子点结合起来构建核壳纳米结构纳米线阵列太阳能电池，可以增大光吸收范围，提高太阳能电池的光吸收和载流子传输效率。然而，在量子点纳米线阵列上制备过氧化物吸收层往往会出现粗糙度高、晶格缺陷多等问题，对光伏性能产生负面影响。反溶剂法是提高过氧化物质量的常用技术。反溶剂的温度变化会改变溶解度，影响过氧化物的反应速率和晶体形成过程，从而影响其光伏性能。本研究通过控制反溶剂（甲苯）的温度，提高了核壳纳米结构纳米线阵列中包晶石的质量。实验结果表明，随着甲苯温度的升高，光伏性能逐渐提高。当甲苯温度保持在 75 ℃ 时，器件的光电性能显著提高，效率达到 12.64%，超过了未进行任何反溶剂改性的效率。随着反溶剂温度的升高，纳米线阵列对可见光和近红外光谱的吸收增强，从而促进了光生载流子的高效生成。此外，纳米线阵列中的缺陷逐渐减少，从而降低了载流子的重组。这些发现为推动核壳纳米结构纳米线阵列太阳能电池的发展提供了宝贵的启示。

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引用次数: 0

Comparative study of NiO based core-shell nanocomposites to high performance supercapacitor electrode materials 基于氧化镍的核壳纳米复合材料与高性能超级电容器电极材料的比较研究

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-11 DOI: 10.1016/j.physe.2024.116121

Jhalak Gupta , Arham S. Ahmed , Pushpendra , Ameer Azam

In this research work, we prepared NiO@SnO₂ (N1), NiO@ZnO (N2) and NiO@MnO₂ (N3) core-shell nanocomposites using sol-gel route. Prepared samples were investigated for their different properties employing various characterization techniques. The morphology and structure of the nanocomposites were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform Infrared Spectroscopy, X-ray diffraction analysis. Furthermore, the optical properties were analyzed using UV–Vis Spectroscopy, Photoluminescence Spectroscopy. In addition, the supercapacitive performances were examined by cyclic voltammogram (CV), galvanostatic charge-discharge(GCD) and electrochemical impedance spectroscopy (EIS). The electrochemical results indicate that all the prepared composites exhibits good electrochemical performance but N2 depicts superior results among all. The specific capacitance obtained for N2 is 720 F/g at 1 A g⁻¹ and excellent cycling stability (96.5 % retention after 6000 cycles at 1 A g⁻¹). Therefore, this wok offers meaningful reference for supercapacitor applications in the future.

在这项研究工作中，我们采用溶胶-凝胶法制备了 NiO@SnO2（N1）、NiO@ZnO（N2）和 NiO@MnO2（N3）核壳纳米复合材料。利用各种表征技术对制备的样品进行了不同性质的研究。透射电子显微镜、X 射线光电子能谱、傅立叶变换红外光谱和 X 射线衍射分析对纳米复合材料的形貌和结构进行了表征。此外，还利用紫外可见光谱和光致发光光谱分析了纳米复合材料的光学特性。此外，还通过循环伏安图（CV）、电静态充放电（GCD）和电化学阻抗谱（EIS）对超级电容器性能进行了检测。电化学结果表明，所有制备的复合材料都表现出良好的电化学性能，但其中 N2 的电化学性能更优。在 1 A g-1 的条件下，N2 的比电容为 720 F/g，循环稳定性极佳（在 1 A g-1 条件下循环 6000 次后，电容保持率为 96.5%）。因此，这种炒锅为超级电容器的未来应用提供了有意义的参考。

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引用次数: 0

Modulation of electronic and thermal properties of boron phosphide nanotubes under electric and magnetic fields 电场和磁场下磷化硼纳米管的电子和热特性调制

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-10 DOI: 10.1016/j.physe.2024.116125

Nooshin Rashidi , Rostam Moradian

This work theoretically investigates the thermoelectric properties of boron phosphide nanotubes (BPNTs) using the tight-binding model, Green function method, and Kubo formalism, focusing on a zigzag BPNT with indices (20, 0). The tight binding parameters obtained by matching its band structure with calculated density functional theory band structure. The study examines the effects of transverse electric fields and axial magnetic fields on various physical properties, such as band structure, density of states (DOS), heat capacity, magnetic susceptibility, and other thermoelectric properties. BPNTs consistently show semiconducting properties with a nearly 1 eV direct band gap. The electronic properties of BPNTs are significantly affected by applied electric field, which at very strong strengths can induce a semiconducting to metallic phase transition. In contrast, the magnetic field leads to the splitting of energy bands, especially around the Fermi level. The DOS also changes with the electric field, including variations in the position, intensity, and number of DOS peaks. The thermal properties and thermoelectric performance of BPNTs are temperature-dependent. Increasing of excited electrons thermal energy cause more occupation of high energy levels in the conduction bands. The electric field further enhances the thermal properties of BPNTs by modifying their electronic properties and reducing the band gap. Stronger electric fields cause a noticeable enhancement in the BPNTs thermal properties because it is increasing the concentration of excited charge carriers. This aspect is crucial for improving the thermoelectric efficiency of BPNTs, making them more competitive for practical applications.

本研究以指数为 (20, 0) 的人字形磷化硼纳米管（BPNT）为研究对象，采用紧结合模型、格林函数法和 Kubo 形式主义对其热电性能进行了理论研究。通过将其带状结构与计算的密度泛函理论带状结构相匹配，获得了紧密结合参数。研究考察了横向电场和轴向磁场对各种物理性质的影响，如带结构、态密度（DOS）、热容量、磁感应强度和其他热电性能。BPNT 始终具有半导体特性，直接带隙接近 1 eV。BPNTs 的电子特性受到外加电场的显著影响，在极强的电场强度下，可诱导从半导体到金属的相变。相反，磁场会导致能带分裂，尤其是在费米级附近。DOS 也会随着电场的变化而变化，包括 DOS 峰的位置、强度和数量的变化。BPNT 的热特性和热电性能与温度有关。激发电子热能的增加会导致传导带中的高能级被更多占据。电场通过改变 BPNTs 的电子特性并减小带隙，进一步增强了其热特性。较强的电场会明显增强 BPNTs 的热性能，因为它会增加激发电荷载流子的浓度。这对于提高 BPNTs 的热电效率至关重要，从而使其在实际应用中更具竞争力。

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引用次数: 0

A metasurface for linear-to-circular polarization conversion and sensing based on quasi-BIC 基于准 BIC 的线-圆偏振转换和传感元表面

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-10 DOI: 10.1016/j.physe.2024.116128

Fa-Zhan Liu, Si-Yuan Liao, Qi-Juan Li, Jing-Wei Huang, Hai-Feng Zhang

This work presents a multifunctional metastructure (MS) which realizes linear to circular polarization conversion and sensing function based on quasi-bound states in the continuum (quasi-BIC). MS is made of silicon dioxide as substrate, and silicon as surface material, by etching cross holes and square holes on it to form a 2×2 structure, through the transmission of terahertz (THz) band, to form an ultrahigh quality factor (Q-factor), and realize the conversion of linearly polarized waves to circularly polarized ones. At 178.190 THz, it achieves a Q value of 2969, and in the range 178.193 TH to 178.200 THz, the axial ratio (AR) is less than 3 dB and the insertion loss is less than 0.0001. In addition, by changing the permittivity of the surrounding environment, the minimum of the output wave will produce a good linear frequency shift. Using this feature, the given device can also be used as a dielectric constant sensor to detect air quality. The device has a sensing sensitivity (S) of 6.415 THz RIU⁻¹ and a figure of merit (FOM) of 106.9. The parameters (H, w₂, L₂, g₂), incidence angle (θ) and the polarization angle (φ) are discussed. The effects of different parameters on the Q-factor and AR were analyzed, which helped to select the optimal parameters. The design can also be used in communication and biosensing.

本研究提出了一种多功能元结构（MS），它基于连续体中的准束缚态（quasi-BIC）实现了线性极化到圆形极化的转换和传感功能。MS 以二氧化硅为衬底，硅为表面材料，通过蚀刻十字孔和方孔形成 2×2 结构，通过太赫兹（THz）波段的传输，形成超高品质因数（Q 因子），实现线偏振波到圆偏振波的转换。在 178.190 THz 时，它的 Q 值达到 2969，在 178.193 TH 至 178.200 THz 范围内，轴向比 (AR) 小于 3 dB，插入损耗小于 0.0001。此外，通过改变周围环境的介电常数，输出波的最小值将产生良好的线性频移。利用这一特点，该装置还可用作介电常数传感器来检测空气质量。该装置的传感灵敏度（S）为 6.415 THz RIU-1，优点系数（FOM）为 106.9。对参数（H、w2、L2、g2）、入射角（θ）和偏振角（φ）进行了讨论。分析了不同参数对 Q 因子和 AR 的影响，有助于选择最佳参数。该设计还可用于通信和生物传感。

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引用次数: 0

Design of spintronic devices based on adjustable half-metallicity induced by electric field in A-type antiferromagnetic bilayer NiI2 基于 A 型反铁磁双层 NiI2 中电场诱导的可调半金属性设计自旋电子器件

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-10 DOI: 10.1016/j.physe.2024.116129

Shao-Chong Yin , Jing-Xin Yu , Xiu-Ying Liu , Xiao-Dong Li , Jing Chang

Exploring the attainment of half-metallic behavior in two-dimensional (2D) materials through external perturbations is a popular area of current research. In this work, we demonstrate, using first-principles calculations, that bilayer NiI₂ (bi-NiI₂) is an A-type antiferromagnetic (AFM) semiconductor with an indirect bandgap of 0.86 eV, with the most stable configuration being the AB stacking mode. Upon the application of a vertical electric field, the material transforms from its original semiconducting state into a half-metallic state. Moreover, the spin polarization reverses its orientation whenever the direction of the electric field is altered. This intriguing behavior has inspired us to design a spintronic device based on the A-type AFM bi-NiI₂. By employing nonequilibrium Green's function (NEGF) combined with density functional theory (DFT) calculations, we find that the device achieves ON/OFF switching by applying vertical electric fields in parallel or anti-parallel configurations in the two leads. The device displays 100 % spin polarization in the parallel configuration (PC) scenario, driven by bias voltage or temperature differences. Utilizing either the parallel or antiparallel configuration (APC) for ON/OFF switching enables the device to exhibit tunneling magnetoresistance (TMR) of up to 1.45 × 10¹⁰ % due to bias voltage and up to 10¹¹ % thermal TMR arising from temperature differences between the leads. These findings highlight the potential of NiI₂ and A-type AFM bilayers in the design of spintronic devices.

探索通过外部扰动在二维（2D）材料中实现半金属行为是当前研究的一个热门领域。在这项研究中，我们利用第一原理计算证明，双层 NiI2（bi-NiI2）是一种 A 型反铁磁性（AFM）半导体，其间接带隙为 0.86 eV，最稳定的构型是 AB 堆积模式。当施加垂直电场时，这种材料会从原来的半导体状态转变为半金属状态。此外，只要改变电场方向，自旋极化就会反转方向。这一引人入胜的行为启发我们设计一种基于 A 型 AFM 双 NiI2 的自旋电子器件。通过采用非平衡格林函数（NEGF）和密度泛函理论（DFT）计算，我们发现该器件可以通过在两条引线上施加平行或反平行配置的垂直电场来实现导通/关断开关。在平行配置（PC）情况下，该器件在偏置电压或温差的驱动下显示出 100% 的自旋极化。利用平行或反平行配置（APC）进行导通/关断开关，可使器件因偏置电压而表现出高达 1.45 × 1010 % 的隧穿磁阻（TMR），因引线之间的温差而表现出高达 1011 % 的热 TMR。这些发现凸显了 NiI2 和 A 型 AFM 双层膜在设计自旋电子器件方面的潜力。

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引用次数: 0

Resonant tunneling properties of laser dressed hyperbolic Pöschl-Teller double barrier potential 激光穿透双曲波氏-泰勒双势垒的共振隧道特性

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-09 DOI: 10.1016/j.physe.2024.116126

Mehmet Batı

We examine the resonant tunneling properties of the laser-dressed hyperbolic Pöschl-Teller double quantum barrier structure. We use the non-equilibrium Green's function method to investigate structure parameters and electric field bias on the transmission properties of the system. The transmission probabilities and resonance energy levels are significantly influenced by the well widths and barrier heights. The barrier height increases, resonance energy levels shift toward higher values, and the resonance peak width narrows, leading to sharper and more selective tunneling behavior. Our results show that increasing the electric field bias leads to a decrease in the transmission probability at the first resonance peak, but this effect is not as strong for the subsequent peaks. Moreover, we find that changes in the laser field's parameter and structure parameters allow for fine control over the electronic spectra, allowing for modifications like red or blue shifts based on particular needs. The significance of comprehending the interaction among structural factors, external fields, and transmission qualities in quantum barrier structures is highlighted by our research, providing valuable information for the development and enhancement of electronic and optoelectronic systems with customized functionality. Our findings show the laser field has a considerable impact on resonant tunneling properties, opening the door to new device applications.

我们研究了激光压制双曲波氏-泰勒双量子势垒结构的共振隧穿特性。我们使用非平衡格林函数法研究了结构参数和电场偏置对系统传输特性的影响。透射概率和共振能级受到阱宽和势垒高的显著影响。势垒高度增加，共振能级向更高值移动，共振峰宽度变窄，从而导致更尖锐和更有选择性的隧道行为。我们的研究结果表明，增加电场偏置会导致第一个共振峰的传输概率降低，但这种效应对后续峰的影响并不强烈。此外，我们还发现，通过改变激光场参数和结构参数，可以对电子光谱进行精细控制，从而根据特定需求实现红移或蓝移等修改。我们的研究强调了理解量子势垒结构中结构因素、外部场和传输质量之间相互作用的重要性，为开发和增强具有定制功能的电子和光电系统提供了宝贵的信息。我们的研究结果表明，激光场对共振隧穿特性有相当大的影响，为新器件的应用打开了大门。

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引用次数: 0

Neutral donors confined in semiconductor coupled quantum dot-rings: Position-dependent properties and optical transparency phenomenon 限制在半导体耦合量子点环中的中性供体：位置相关特性和光学透明现象

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-09 DOI: 10.1016/j.physe.2024.116122

N. Hernández , R.A. López-Doria , Y.A. Suaza , M.R. Fulla

Electronic properties of a neutral donor confined in a

GaAs

coupled quantum dot-ring covered by a

{Al}_{0.3} {Ga}_{0.7} As

matrix were calculated using the finite element method under the effective mass and the envelope function approximations. The proposed model is set up to fit a realistic coupled quantum dot-ring geometry revealed by atomic force microscopy images. The results show that the energy levels and the transition energies in the presence of an electric field strongly depend on the donor center’s angular position. Furthermore, the total optical absorption coefficient is calculated within the two-level approximation and the matrix density formalism. The absorption spectrum shows that the system can be tuned between 5 and

30 meV

. Also, an optical transparency effect for different configurations characterized by specific donor center’s angular positions and electric field values is seen. Finally, a novel redshift is observed when the sample temperature increases.

在有效质量和包络函数近似条件下，使用有限元法计算了被 Al0.3Ga0.7As 矩阵覆盖的 GaAs 耦合量子点环中的中性供体的电子特性。所提议的模型是为拟合原子力显微镜图像所揭示的现实耦合量子点环几何形状而建立的。结果表明，在电场作用下，能级和跃迁能强烈依赖于供体中心的角位置。此外，还根据两级近似和矩阵密度形式计算了总的光吸收系数。吸收光谱显示，该系统可以在 5 至 30meV 之间进行调整。此外，在以特定供体中心角位置和电场值为特征的不同配置中，还可以看到光学透明效应。最后，当样品温度升高时，还观察到一种新的红移现象。

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引用次数: 0

Correlation of Valence electron structure and properties of monolayer graphene and MX2 (M=Mo, W; X=S, Se, Te): Empirical Electron Theory (EET) investigation 单层石墨烯和 MX2（M=Mo、W；X=S、Se、Te）的价电子结构和性质的相关性：经验电子理论 (EET) 研究

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-08 DOI: 10.1016/j.physe.2024.116124

Xinze Wang, Yongquan Guo, Boyang Li, Yichen Feng, Wei Tang

The atomically thin layers of transition-metal dichalcogenide (TMDC) materials have garnered considerable attention due to their exceptional electrical, optical, mechanical, and thermal properties. Hence, it is important to investigate the mechanism of their excellent properties. In this paper, the study is focused on the correlation between valence electron structures (VESs) and mechanical as well as thermal properties of graphene and MX₂ (M = Mo, W; X = S, Se, Te) for revealing their essential mechanisms of properties with an empirical electron theory (EET). A model of Young's modulus is built for the monolayer graphene and MX₂ (M = Mo, W; X = S, Se, Te) based on the VES, which has been verified by the observed ones of elements in the 4th to 6th periods in the periodic table of elements. The calculated bond lengths and mechanical and thermal properties of graphene and MX₂ are in good agreement with experimental ones. The study reveals that the thermal and mechanical properties of MX₂ strongly depend on their valence electron structures. It shows that the melting point, cohesive energy, thermal conductivity, and Young's modulus are modulated by covalence electron pair n_A, the averaged covalence electron per atom n_c/atom, covalence electron pair n_A and linear density of covalent electron on the strongest bond ρ_l, respectively. The study helps explain the thermal and mechanical properties of two-dimensional (2D) materials and also supplies a reference for their design with high performance by modulating their valence electron structures.

过渡金属二卤化物（TMDC）材料的原子薄层因其卓越的电学、光学、机械和热学特性而备受关注。因此，研究其优异特性的机理非常重要。本文的研究重点是石墨烯和 MX2（M = Mo、W；X = S、Se、Te）的价电子结构（VES）与机械性能和热性能之间的相关性，从而利用经验电子理论（EET）揭示其性能的本质机理。基于 VES，建立了单层石墨烯和 MX2（M = Mo、W；X = S、Se、Te）的杨氏模量模型，并通过观测元素周期表中第 4 至第 6 周期元素的杨氏模量进行了验证。计算得出的石墨烯和 MX2 的键长、机械性能和热性能与实验结果十分吻合。研究表明，MX2 的热性能和机械性能在很大程度上取决于其价电子结构。研究表明，熔点、内聚能、热导率和杨氏模量分别受共价电子对 nA、每个原子的平均共价电子 nc/原子、共价电子对 nA 和最强键上共价电子的线性密度 ρl 的调节。这项研究有助于解释二维（2D）材料的热性能和机械性能，也为通过调节其价电子结构设计高性能材料提供了参考。

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引用次数: 0

Multi-layer nanoring array-based ultra-wideband solar absorber for photothermal conversion 基于多层纳米阵列的光热转换超宽带太阳能吸收器

IF 2.9 3区物理与天体物理 Q3 NANOSCIENCE & NANOTECHNOLOGY

Physica E-low-dimensional Systems & Nanostructures

Pub Date : 2024-10-05 DOI: 10.1016/j.physe.2024.116123

Jiaxing Jiang , Yingting Yi , Qianju Song , Zao Yi , Can Ma , Qingdong Zeng , Tangyou Sun , Shubo Cheng , Yougen Yi , Majid Niaz Akhtar

In this work, based on the finite difference time domain method, we propose and investigate an efficient nanoscale solar absorber based on multilayer nanorings. The absorber is made up of a 4-layer TiO₂-TiN nanoring array, a TiO₂ insulating layer and a Ti substrate, all of which are high-melting materials. The absorber exhibits an absorption efficiency surpassing 95 % across a wavelength span of 280–4000 nm, thereby attaining a bandwidth of 3720 nm. Additionally, it maintains an average absorption efficiency of 98.8 % throughout the entire wavelength spectrum. Furthermore, calculations reveal that the absorber possesses a solar spectrum-weighted absorption of up to 99 %. The analysis of the electric field distribution indicates that the observed intense absorption is attributed to the plasmonic resonance phenomenon, along with the near-field coupling effects exhibited by the multi-turn nanorings. In addition, our calculations revealed a remarkably high thermal radiation efficiency for this absorber, specifically 99.2 % at 2000 K and 98.9 % at 1500 K, respectively. Therefore, we then calculated the photothermal conversion efficiency of the absorber. At the solar concentration factor C = 1000, the photothermal conversion efficiency surpasses 90 % across the entire temperature range. At C = 100, it is still greater than 80 % at 1000 K. At C = 10, it is still greater than 80 % at 700 K. And at C = 1, it is still greater than 80 % at 500 K. These results indicate that absorbers can be used in a variety of environments. Furthermore, the absorber sustains its superior absorption capabilities at wider solar radiation angles, demonstrating insensitive properties to polarization variations and robust tolerance to manufacturing inaccuracies. These exceptional attributes render it highly suited for diverse applications in solar energy harvesting and photothermal transformation.

在这项工作中，我们基于有限差分时域法，提出并研究了一种基于多层纳米环的高效纳米级太阳能吸收器。该吸收器由 4 层 TiO2-TiN 纳米环阵列、TiO2 绝缘层和 Ti 衬底组成，所有材料均为高熔点材料。该吸收器在 280-4000 纳米波长范围内的吸收效率超过 95%，从而达到 3720 纳米的带宽。此外，它在整个波长范围内的平均吸收效率为 98.8%。此外，计算显示，该吸收器的太阳光谱加权吸收率高达 99%。对电场分布的分析表明，观察到的高吸收率可归因于质子共振现象以及多圈纳米环表现出的近场耦合效应。此外，我们的计算还表明，这种吸收器的热辐射效率非常高，在 2000 K 和 1500 K 时分别达到 99.2% 和 98.9%。因此，我们接着计算了该吸收器的光热转换效率。当太阳浓度系数 C = 1000 时，光热转换效率在整个温度范围内均超过 90%。在 C = 100 时，1000 K 时的光热转换效率仍大于 80%；在 C = 10 时，700 K 时的光热转换效率仍大于 80%；在 C = 1 时，500 K 时的光热转换效率仍大于 80%。此外，这种吸收器还能在更宽的太阳辐射角度下保持其卓越的吸收能力，显示出对偏振变化不敏感的特性以及对制造误差的强大耐受力。这些优异的特性使其非常适合于太阳能收集和光热转换领域的各种应用。

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