- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Wrinkled titanium nitride nanocomposite for robust bendable electrodes
摘要： Electrical contacts and interconnections are critical components for all electronic devices. Bendable electrodes with enhanced electro-mechanical properties are highly desirable to develop innovative wearable electronic devices. Herein we report on a fabrication method for robust bendable coatings based on titanium nitride (TiN) thin films and silver nanowires (Ag NWs). TiN and TiN-AgNWs nanocomposites were deposited on polyethylene terephthalate (PET) substrates using a plasma enhanced pulsed laser deposition (PLD) technique. The resulting TiN coatings exhibit excellent adhesion to PET and their sheet resistance can be tuned using a dual frequency PLD process and further decreased by incorporating Ag NWs into the TiN layers. Sample sheet resistance was decreased down to values as low as 3.5 Ω/□, thanks to the formation of TiN-AgNWs nanocomposites. The electro-mechanical robustness of TiN based coatings were evaluated by four-probe resistance measurements in situ under cyclic bending tests. We show that the TiN-AgNWs nanocomposites surpass both ITO and Ag NWs coatings in terms of mechanical robustness and electrical conductivity respectively. These nanocomposites withstand high strain fatigue loading up to ε = 2.6%, keeping RS below 5 Ω/□. The data demonstrates that the incorporation of Ag NWs in TiN coatings improve the mechanical robustness, limiting the crack growth and propagation, with low optical transmittance decrease (≈11%). These results indicate that Ag NWs based nanocomposites are attractive materials for flexible electronic devices.
关键词： mechanical strain,titanium nitride,nanocomposite,ITO,flexible electrode,silver nanowires
更新于2025-09-19 17:13:59
-
Synchronous Enhancement for Responsivity and Response Speed in In2Se3 Photodetector Modulated by Piezoresistive Effect
摘要： Although ultra-high single performance indicators have been achieved based on two-dimensional(2D) semiconductors, the comprehensive performances of the photodetectors of them are not so desirable. Note that the response speed and responsivity are two key figures of merit for photodetectors, while these two parameters are always mutually suppressive and can not be synchronously satisfied. Here, we proposed a feasible strategy that can simultaneously improve the responsivity and response speed of In2Se3-based photodetectors, by applying the mechanical strain and producing the piezoresistive effect, which can synergistically modulate the band structure and boost the overall photodetecting performances. Through studying the optoelectronic properties of In2Se3 photodetector under strain modulations, we found that the responsivity under 0.65% tensile strain is improved by almost 68.6% on average while responsivity under 0.65% compressive strain is lowered by about 57.3% in the wavelength range of 200-1000 nm. More importantly, the response speed of the In2Se3-based photodetector under two different mechanical strains rises distinctly (from 244 to 214 and 180 μs, accordingly). The strain-engineering can accommodate the band structure and enhance the electric and optical properties of the semiconducting crystals, ultimately realizing high-performance photodetectors. The strategy proposed in this work for improving the performance of photodetectors provides a promising route to practical applications in next-generation optoelectronic devices.
关键词： photoconductor,mechanical strain,Schottky barrier,van der Waals,piezoresistive effect
更新于2025-09-11 14:15:04
-
I–V characteristics and conductance of strained SWCNTs
摘要： We present a new procedure to investigate the I–V characteristics and the conductance for strained SWCNTs. These electronic transport properties have been studied theoretically at zero temperature for zig-zag, armchair and chiral SWCNTs under the effect of the uniaxial tension and torsional strain. The analytical expression of the energy spectrum in the tight binding approximation has been used to calculate the induced current and the conductance through Landauer–Büttiker formalism. It is shown that the conductance for unstrained CNTs at initial values of the voltage can take discrete values which are equal to zero and 4 (e2/h) for semiconducting and conducting SWCNTs respectively. The emergence of the kinks in the I–V characteristics is due to the discrete electronic spectrum in the SWCNTs. The location and number of kinks are changeable under the effect of strain process. The conductance in a strained armchair (5, 5) CNT decreases to zero under torsional strain, consequently, it will transform the conducting SWCNTs at a threshold value of strain to a semiconducting SWCNT. In contrast, by applying the uniaxial tension on the armchair (5, 5) CNT, the conductance does not change absolutely. There is a different behavior can be observed by applying the strain on zig-zag (10, 0) CNT, where the conductance decreases rapidly and slightly under the in?uence of uniaxial tension and torsional strain, respectively. We found that the conductance of chiral (10, 9) CNT is not signi?cantly affected by applying the strain under consideration. More interestingly, the band structure of chiral (10, 9) CNT under uniaxial tension and torsional strain have been investigated within the tight binding approximation.
关键词： I–V characteristics,Mechanical strain,Tight binding approximation,SWCNT,Conductance
更新于2025-09-10 09:29:36
-
Thermoelectric performance of monolayer InSe improved by convergence of multivalley bands
摘要： We theoretically investigate a possibility of improving the thermoelectric performance of monolayer InSe through convergence of multivalley energy bands, in which some distinct valleys become almost degenerate. The convergence of energy bands is achieved by applying mechanical strain. We find that the thermoelectric power factor of monolayer InSe can be significantly enhanced by nearly a factor of 3 through the band convergence in both valence (p-type) and conduction (n-type) bands under a biaxial compressive stress of about 1.16 GPa. However, the maximum enhancement of the figure of merit ZT in the p-type and n-type InSe differs each other depending on how the valleys converge in each case. The optimal scenario is that the heavy valleys approach the light valleys in the band convergence, which leads to an increase in the power factor and, at the same time, a decrease in the thermal conductivity of an electron. This optimal condition can be obtained in the strained n-type InSe that gives the largest enhancement of ZT as high as 230% ZT of unstrained InSe. In contrast, the enhancement of ZT in the strained p-type InSe, which exhibits opposite valley convergence (light valleys joining heavy ones), gives only 26% ZT of unstrained InSe.
关键词： mechanical strain,thermoelectric performance,power factor,figure of merit,multivalley bands,monolayer InSe
更新于2025-09-10 09:29:36
-
Valley polarization and biaxial strain dependent conductivity of WS2/SrRuO3(1?1?1) heterostructures
摘要： The electronic structures of monolayer WS2 on top of bilayer SrRuO3(1 1 1) are studied by first-principles calculations with spin-orbital coupling. The electronic properties can be influenced by stacking patterns of WS2/SrRuO3(1 1 1) heterostructures. Meanwhile, the valley polarization can be induced in monolayer WS2 due to the broken time-reversal symmetry by the proximity to bilayer SrRuO3(1 1 1). With particular stacking patterns, larger valley splitting of monolayer WS2 obtained in A1, A3, A4 and A5 models is 11.2, 11.3, 11.1 and 11.1 meV, respectively. Moreover, with biaxial strains, the conductivity of monolayer WS2 can be effectively modulated. The Fermi level moves to a higher energy by appling tensile strains. Then the conductivity of WS2 is governed by the valley states. In addition, the mechanical strains can modify the valley polarization and band gap effectively, showing potential applications in spintronic and valleytronic devices.
关键词： Anomalous Hall effect,Valley polarization,Mechanical strain,Transition metal dichalcogenide
更新于2025-09-09 09:28:46