Maskless Formation of Conductive Carbon Layer on Leather for Highly Sensitive Flexible Strain Sensors

Abstract

Development of strain sensors on flexible and breathable leather or textile has potential applications in Internet of Things, human–machine interfaces, and motion detection. Nevertheless, the fabrication of strain sensors with high performance on the above substrates in a maskless, scalable, and highly efficient manner is still a challenge. In this study, highly sensitive strain sensors are mask‐freely fabricated on leather by a highly efficient and scalable laser direct writing (LDW) technique in open air without using any additional precursors. The strain sensors are constructed by the carbon flake synthesized by LDW carbonization of collagen fibers in the leather. The LDW carbonized leather‐based device provides maximum sensitivities of ≈2009.5 and ≈50.9 for tension and compression strain detection, respectively. Additionally, the device has a minimum detection strain of 0.005% and a good mechanical stability over 10 000 bending cycles. The high performance of the flexible strain sensors as well as the developed maskless, scalable and highly efficient LDW technique endows the promising applications of the devices in human motion monitoring and external stimuli detection.

3D Printed Reduced Graphene Oxide/Elastomer Resin Composite with Structural Modulated Sensitivity for Flexible Strain Sensor

“…In existing researches, many scalable fabrication methods have been proposed to fabricate flexible strain sensors, such as photolithography, [20,21] spraying, [22] laser direct writing, [23,24] inkjet printing, [25] pencil-drawn method, [26] and dip-coating method. [27] These methods often require complicated procedures or are not efficient or cost-effective.…”

Crosstalk‐Free, High‐Resolution Pressure Sensor Arrays Enabled by High‐Throughput Laser Manufacturing

“…[ 18,19 ] Depending on the intensity of the laser power, one can use a laser to cut materials in various structures [ 20,21 ] or induce chemical reactions in materials, for example, converting carbon‐based polymers to graphene. [ 22–27 ] Here we use a UV laser to create a sensor array from a polymeric multi‐layer stack. We first use low laser power to generate isolated piezoresistive 3D graphene pixels and then turn up the laser power to cut through the active and substrate layers and leave behind an interconnect pattern to connect individual pixels.…”

“…[18,19] Depending on the intensity of the laser power, one can use a laser to cut materials in various structures [20,21] or induce chemical reactions in materials, for example, converting carbon-based polymers to graphene. [22][23][24][25][26][27]…”

Laser Direct Writing of Flexible Sensor Arrays Based on Carbonized Carboxymethylcellulose and Its Composites for Simultaneous Mechanical and Thermal Stimuli Detection

“…32 Liu's group reported a LDW sensor fabricated on polyimide/paper bilayer structure for force and humidity detection. 33 In our previous work, strain and pressure sensors have been fabricated on Ecoflex, 29 textile, 28 and leather 34 by LDW. Although LDW has been regarded as a highly efficient method to fabricate flexible electronics in a mask-free way, a large portion of the above studies only focuses on LDW carbonization of substrates (e.g., PI, PDMS) 35,36 for flexible sensors.…”