- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Ultra-flexible perovskite solar cells with crumpling durability: toward a wearable power source
摘要： Perovskite materials hold great potential as photovoltaic power sources for portable devices owing to their mechanical flexibility and high performance; however, the flexibility and e?ciency require further improvement to attain practical viability. We investigated the mechanical fracture behavior of polycrystalline perovskite films by varying the substrate thickness and applying the neutral plane concept. This enabled us to fabricate a crack-free perovskite film on an ultra-thin substrate (B2.5 mm) and to demonstrate ultra-flexible solar cells with high e?ciency (17.03%) with unprecedented flexibility sustained after 10 000 cycles of bending at a 0.5 mm radius. This represents a high e?ciency of 13.6% for large-area flexible perovskite solar cells (1.2 cm2), fabricated by using a hybrid transparent electrode composed of a metal mesh grid and conducting polymer. Using a protective layer to achieve the neutral plane concept, our ultra-flexible perovskite solar cells are demonstrated to be durable even after 100 crumpling cycles. Our approach paves the way to fabricate flexible perovskite solar cells for portable power sources.
关键词： wearable power source,Perovskite solar cells,mechanical durability,neutral plane concept,flexible
更新于2025-11-21 10:59:37
-
Depletion Layer Built-In Field at (1?100), (0001), and (000?1) GaN/Water Junction and Its Role in Semiconductor Nanowire Water Splitting
摘要： The nature of specific GaN plane/water interfaces under external bias and illumination can influence photoelectrolysis efficiency using GaN nanowires. Studies of Ga-polar, N-polar, and m-plane GaN interfaces with deionized water allow determining differences between surfaces corresponding to different nanowire facets. They are investigated under external bias conditions to reveal the profile of Fermi level localization through analysis of Franz–Keldysh oscillations using electrolyte electroreflectance (EER) technique in a specially designed measurement chamber. Calculation of the potential barrier height is also possible. EER study shows differences between surface densities of states (SDOS) at distinct GaN planes. One broad SDOS is identified near the conduction band in case of ±c-plane and related to Ga adatom reconstruction and β-Ga2O3 presence at the GaN electrode. Two narrow SDOS singularities are found at the m-plane one of which is localized near the middle of the bandgap and allows to generate approximately two times higher surface potential barrier than in case of polar surfaces at zero-bias conditions. This suggests that n-type GaN nanowires can enhance carrier separation at sidewalls and refine the oxygen evolution rate. Additionally, a voltage-controlled hysteresis loop of Fermi level localization is detected at the Ga-face GaN/water interface.
关键词： photoelectrolysis,m-plane,surface states,GaN,c-plane
更新于2025-09-23 15:23:52
-
[IEEE 2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED) - Tbilisi, Georgia (2018.9.24-2018.9.27)] 2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED) - The Nonuniquness of Solutions to the Synthesis Problems of Plane Array by the Prescribed Amplitude Directivity Pattern
摘要： Studies of a nonlinear synthesis problem for plane equidistant array by the prescribed amplitude directivity pattern (DP) are presented. A characteristic feature of problems of this class is the non-uniqueness and branching of solutions depending on the physical parameters of array. The existence of several types of real solutions is shown. More effective complex solutions branch off from such solutions. The methods of finding the curves of branching the solutions and the numerical algorithms to search the optimal synthesized amplitude DPs are presented.
关键词： amplitude DP,non-uniqueness and branching of solutions,curves of branching,Synthesis problem,plane array
更新于2025-09-23 15:23:52
-
Full wave analysis of plane wave diffraction by a finite sinusoidal grating: E-polarization case
摘要： Plane wave diffraction studies of a finite sinusoidal grating have previously assumed that the grating length is large in wavelengths and the depth of its corrugations is small compared to a wavelength. This paper introduces a rigorous technique, the Method of Analytical Regularization (MAR), which removes these restrictions. The solution obtained by this method is free from limitations on the parameters of sinusoidal grating and possesses the capability to achieve predetermined accuracy of computations uniformly in a wide frequency band. The results of previous studies, which employed the Wiener-Hopf technique combined with a perturbation method, are compared with those obtained by the MAR; excellent concordance of results in the common parameter regimes of applicability of both methods is found. The different regimes of applicability of each approach are identified; within these, the MAR provides effective and efficient solutions to benchmark problems for testing other approximate techniques.
关键词： efficient computational algorithm in wide frequency band,scattering of E-polarized plane wave,method of analytical regularization,Floquet modes for finite grating,finite sinusoidal grating,Wiener-Hopf technique combined with perturbation method
更新于2025-09-23 15:23:52
-
New blue phosphorescence from trifluorosulfonyl-substituted iridium complexes
摘要： For color-pure phosphorescence organic light emitting diodes (PHOLEDs), we synthesized the trifluoromethyl sulfonyl substituted ligand and two new blue Iridium complexes with perfluoro-sulfonyl group (SOCF3pic and SOCF3mpic). The both iridium complexes showed similar photophysical and thermal properties while the HOMO energy leves of two Iridium complexes slightly differnet to be -5.84 eV for SOCF3pic and -5.74 eV for SOCF3mpic, respectively. The device with the SOCF3mpic dopant exhibited higher device efficiencies of 7.17 cd/A and 3.7 % compared to that with the SOCF3pic dopant (4.03 cd/A and 2.78 %). Two-dimensional GIXD images of scattered X-ray intensity from surface to full depth for SOCF3pic-doped and SOCF3mpic-doped TCTA:4PTPS films were characterized for preferential orientation along the out-of-plane direction.
关键词： preferential orientation along the out-of-plane direction,blue phosphorescence,iridium complex,grazing incidence wide-angle X-ray diffraction,organic light emitting diodes
更新于2025-09-23 15:23:52
-
Polarized THz Emission from In-Plane Dipoles in Monolayer Tungsten Disulfide by Linear and Circular Optical Rectification
摘要： Recent advances in the development of polarized terahertz (THz) emission from nanomaterials have not only opened up a new “TeraNano” interdiscipline but also provided a new tool for nonlinear optical process research. Herein, THz radiation mechanism of monolayer tungsten disulfide (WS2) is first investigated by both linear and circular polarization laser excitations at room temperature. The results reveal that polarized THz emission is dominated by the optical rectification based on in-plane nonlinear dipoles, which is totally different from that of bulk WS2. The mechanism is verified by the azimuthal angle and pump polarization angle dependence of THz emission in both experiment and theory. Furthermore, controllably elliptically polarized THz emission is observed with the maximum ellipticity of ≈0.52 based on nonresonant nonlinear process under the circularly polarized excitation. A clear understanding of THz radiation mechanism of 2D materials will facilitate further design, optimization, and polarization control of integrable 2D THz optoelectronics.
关键词： THz radiation,monolayer WS2,in-plane nonlinear dipoles,optical rectification,elliptically polarized THz emission
更新于2025-09-23 15:23:52
-
Angle-dependent excitonic luminescence in semiconductor microtube cavity: The self-absorption effect
摘要： We obtain a Liouville theorem for the semilinear fractional CR covariant equation Pα/2u = up (1 ≤ α < 2) on the Heisenberg group Hn. For this purpose, we extend the fractional equation to sub-Laplace Neumann problem on Hn × R+. Then the conclusion is derived by applying the CR inversion and moving plane method to the Neumann problem. Our result is a generalization for the corresponding one to P1/2u = up.
关键词： Liouville theorem,moving plane method,fractional CR covariant equation,Heisenberg group,CR inversion
更新于2025-09-23 15:23:52
-
A Quantum Image Watermarking Scheme Based on Two-Bit Superposition
摘要： Quantum watermarking technology protects copyright by embedding an invisible quantum signal in quantum multimedia data. This paper proposes a two-bit superposition method which embeds a watermark image (or secret information) into a carrier image. Firstly, the bit-plane is used to encrypt the watermark image. At the same time, the quantum expansion method is used to extend the watermark image to the same size with the carrier image, and then the image is encrypted through the Fibonacci scramble method again. Secondly, the first proposed method is the two bits of the watermark image which is embedded into the carrier image in accordance with the order of the high and lowest qubit, and the second proposed method which is the high bit of the watermark image is embedded to the lowest bit. Then the lowest bit of the watermark image is embedded in carrier image. Third, the watermark image is extracted through 1-CNOT and swap gates, and the watermark image is restored by inverse Fibonacci scramble, inverse expansion method and inverse bit-plane scramble method. Finally, for the validation of the proposed scheme, the signal-to-noise ratio (PSNR), the image histogram and the robustness of the two watermarking methods are analyzed.
关键词： Fibonacci scramble,Swap gates,Superposition,Robustness,Bit-plane scramble
更新于2025-09-23 15:23:52
-
[IEEE 2018 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC) - Xuzhou (2018.7.21-2018.7.24)] 2018 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference (CSQRWC) - Gaussian Beam Scattering from a Sphere on or Near a Plane Surface
摘要： A theoretical procedure is presented for calculating the scattered fields from a sphere on or near a plane surface. The incident Gaussian beam is expanded in series of cylindrical vector wave functions, and the scattered as well as internal fields in series of spherical ones. By using the boundary conditions and the method of moments technique, the unknown expansion coefficients are determined. Numerical results of the normalized differential scattering cross section are given, and the scattering characteristics are discussed concisely.
关键词： sphere above a plane surface,Scattering,Gaussian beam
更新于2025-09-23 15:23:52
-
Optical Energy Characteristics of the Optimal Module of a Solar Composite Parabolic-Cylindrical Plant
摘要： The module of parabolic-cylindrical composite mirror concentrating system (MCS) is created with an optimal aperture angle (U) and relevant optimal size of the focal spot provided by flat mirror elements with the optimal size.
关键词： mirror concentrating systems,heat receiver,focal plane,parabolic-cylindrical concentrator,flat facets,heat carrier
更新于2025-09-23 15:23:52