Laser writing of Cu/Cu O integrated structure on flexible substrate for humidity sensing

Flexible Nonenzymatic Glucose Sensing with One‐Step Laser‐Fabricated Cu2O/Cu Porous Structure

“…Figure a shows a schematic diagram for integrating the sensor. The laser writing is performed by traveling a focused laser beam on a PI substrate covered with the dried Cu 2+ precursor (a mixture of polyvinyl pyrrolidone (PVP, as reducing agent) [ 18,24 ] and Cu(NO 3 ) 2 ). After laser writing, the residual precursor and nonirradiated area can be cleaned using deionized water to obtain the designed patterns.…”

“…[ 16 ] Furthermore, laser writing can also induce the reaction of an ion precursor through photothermal action to synthesize the Cu materials and further assemble them by sintering action. [ 17 ] Various Cu‐based structures have been successfully fabricated for electronic devices such as humidity sensors, [ 18 ] memristors, [ 19 ] and tactile sensors. [ 20 ] In addition to direct laser writing's rapid, maskless, and noncontact processes, its adaptability to various substrates (such as glass, [ 21 ] silicon, [ 22 ] polyimide (PI), [ 17 ] and polycarbonates [ 23 ] ) would extensively enlarge its application.…”

Flexible Gas Sensor Printed on a Polymer Substrate for Sub-ppm Acetone Detection

“…Flexible gas sensor substrates are very promising in the portable exhaled breath analyzers. In recent years, [21] flexible gas sensors have become increasingly attractive due to a number of advantages such as miniaturization, and portable or wearable properties. Flexible gas sensors based on the plastic substrates (plastic polyimide, PI) with titania nanotube (TNT) gas-sensitive layer for carbon monoxide (CO) and ammonia (NH 3 ) detection were reported in 2014 by Jang et al [15].…”

“…The single-walled carbon nanotubes (SWNTs)-Fe 2 O composite films deposited on plastic substrates were investigated as a potential gas sensor for NH 3 , NO and NO 2 detection [18]. Recently, various different gas-sensing applications have been reported, including H 2 S detection with inkjet-printed copper acetate on a flexible plastic substrate [19], ethanol detection with sensor consisting of a 1D TiO 2 nanofiber wrapped in a shell of Bi 2 WO 6 nanosheets [20], and humidity detection of Cu/Cu x O integrated structure on flexible polycarbonate substrates [21]. Table 1 shows a brief summary of these recent studies, and a thorough review of flexible gas sensors can be found in Alrammouz et al [22].…”

Laser‐Patterned Copper Electrodes for Proximity and Tactile Sensors

“…In the process of laser direct patterning, laser beam removes the solvent and ligand, reduces metal ions to form nanoparticles, and in situ anneals nanoparticles to enhance the conductivity of the structure. Due to its compatibility with wide range of materials, laser direct patterning process for many nanomaterials have been reported, including crystallized TiO 2 , graphene, Cu, etc. This provides feasibility for efficiently assembling high‐performance sensors.…”