Stretchable MoS₂ Artificial Photoreceptors for E‐Skin

Abstract

2D materials have been widely applied in flexible electronics but only with limited stretchability, because the metal‐halide bonding is so strong that the materials’ electronic properties will be severely influenced upon tensile strain. Here, a strategy is proposed for the fabrication of ultrastretchable MoS2 photoreceptors based on chemical vapor deposition‐grown or manually stacked multilayer MoS2. Strain‐dependent spectroscopic comparisons of multilayer versus monolayer MoS2 indicate that the strain transfer is suppressed from bottom to top layers owing to interlayer sliding, which is consistent with the density functional theory and molecular dynamics simulations. Thus, the optoelectronic properties of multilayer MoS2 can withstand larger mechanical strain than monolayer MoS2. Leveraging this mechanical feature, ten‐layer MoS2 photodetector is fabricated on polystyrene‐b‐poly (ethylene‐co‐butylene)‐b‐polystyrene elastomer, withstanding ≈50% tensile strain and presenting 32 times higher photoresponsivity than that of monolayer MoS2 under the same stretching condition. Based on large‐area bilayer MoS2 film, 5 × 5 stretchable photodetector array is demonstrated and is capable of working as artificial photoreceptors to control a robotic hand under 16% tensile strain, showing great potential in applications for 2D material‐based electronic skin.

2D-Materials-Based Wearable Biosensor Systems

“…The third type of e-skin is the optical sensor, which converts pressure signals into electrical signals through an optical technique [ 87 , 90 , 102 , 103 ]. Among all the types of sensors, it is superior in its sensitivity, static terms, linearity, and resistance to drift; however, its instability in the worn situation, high-cost manufacturing, and energy intensity limit their applicability in small, simple, and low-power e-skin devices.…”

“…Copyright 2019, Wiley−VCH. ( D ): Current versus source−drain voltage on a single layer of MoS 2 ; illustration of this elastomeric substrate attached to a human wrist for lighting detection and human–machine interaction [ 90 ]. Copyright 2022, Wiley-VCH.…”

Highly Conductive and Underwater Stable Ionic Skin for All‐Day Epidermal Biopotential Monitoring

“…Ionic skin represents a category of artificial skins, which is based on ionic conductors, while electronic skin is based on electrical conductors. [1] In electronic skin, electrical conductors are usually opaque, [2,3] substrate-dependent, [4,6] and cannot be directly used because of their rigidity or high modulus. [7,8] On the contrary, ionic conductors intrinsically possess the skin-feature with homogeneous conductivity.…”

Vanadium defect-engineering in molybdenum disulfide for electrochemical nitrate reduction

“…16,17 As a representative TMD, molybdenum disulde (MoS 2 ) is generally used in sensors, energy storage, electrocatalysis and other elds due to its low cost, potentially large number of active sites, and chemical stability. [18][19][20] Density functional theory (DFT) and experimental study have proved that MoS 2 has great potential for nitrogen reduction. 21 However, its poor conductivity and active sites which are distributed only at the edge limit its catalytic activity.…”