Multilayered Nanometer Thick Films of n-MoS₂ QD/n-MoS₂/p-CuO as p–n Heterojunctions for Self-Powered Flexible Photodetectors

Abstract

The present study has investigated the photoresponse of n-MoS2 QDs/n-MoS2/p-CuO, a hybrid dimensional nanoscale heterostructure fabricated on a flexible Ag-coated Kapton substrate. The fabricated flexible heterostructure demonstrates a significant response toward ultraviolet (UV) (376 nm) to near-infrared (NIR) (1064 nm) wavelengths, even in the self-powered mode. The type-II heterostructure formed between the n-MoS2 and p-CuO layers offers the necessary built-in potential for separating and transporting photogenerated electron–hole pairs. The fabricated flexible nanodimensional heterostructure offers responsivities of 28, 54, and 83 μA/W for illuminating radiations in UV, visible, and NIR regions, respectively, in the self-biased mode. The response times [rise time (τr)/fall time (τf)] for the fabricated flexible heterostructure were found to be 81.12 ms/83.47 ms, 77.36 ms/85.73 ms, and 75.62 ms/81.92 ms for the illumination of radiations lying in the UV, visible, and NIR wavelength regions, respectively. The obtained photoresponse demonstrates that the fabricated MoS2 QDs/n-MoS2/p-CuO hybrid dimensional flexible heterostructure will be a potential candidate for the futuristic era of flexible and ultrarapid photodetection applications.

Ti–Cr–N Nanopyramid/Nitrogen-Doped Carbon Quantum Dot/Stainless Steel Mesh as a Flexible Supercapacitor Electrode

“…Chemically constructed electrode materials amalgamate binders and conductive additives to produce a slurry applied to substrates, resulting in SC TFEs. The manufactured electrodes have disadvantages such as poor adhesion, increased mass loading, lesser purity, and higher internal resistances, which negatively impact their electrochemical performance. , As a result, employing DC magnetron sputtering and electrophoretic deposition techniques, high-purity TFEs can be synthesized by depositing active electrode material directly without binders or additives. − …”

Synergistic Effects of UV Irradiation on a Flexible Ag/NCQDs-MoS2/Ag/Kapton Resistive-Switching Memory Device

“…Such a technology allows the controllability of resistance using both voltage and UV-light pulses. Besides this, developing advanced flexible functional memories has also added significant value in different areas of futuristic wearable, foldable, and implantable technologies. ,− This additional functionality adds a new dimension to the device, enabling it to serve multiple purposes simultaneously. Current technological advances offer various substrates and materials to fabricate flexible devices.…”

“…Recently, two-dimensional (2D) layer materials such as molybdenum disulfide (MoS 2 ) have gained a lot of interest in modern device development due to their excellent flexibility, high mechanical strength, tunable band gap, and optical characteristics. − However, it has been discovered that MoS 2 thin films have in-plane mechanical stiffness comparable to steel, making it an intriguing material for various flexible applications. , In this regard, polyimides such as Kapton have garnered considerable attention due to their unique properties, particularly low Young’s moduli. Furthermore, Kapton demonstrates a high adhesion energy, providing a strong bond for excellent adhesion with thin films. , …”

Direct Transfer of Monolayer MoS2 Device Arrays for Potential Applications in Flexible Electronics

“…The growth of such crystals at high temperatures (>650 °C) often modifies the clean interface of the growth substrate due to charge/ion doping which could hinder their optoelectronic response for transistor applications . For example, recently, we have reported Na + ion doping in the gate dielectric via a salt-assisted CVD method that resulted in large hysteresis in the transfer characteristics of monolayer MoS 2 - and WS 2 -based field-effect transistors (FETs). , Though controlled interfacial engineering in such cases has its own advantages in multibit memory and neuromorphic computing applications, , these CVD-grown samples could be further explored to realize intrinsic transistor properties and flexible electronic applications by transferring them to application-specific target substrates. − …”