Physical and Chemical Sensors on the Basis of Laser-Induced Graphene: Mechanisms, Applications, and Perspectives

Abstract

Laser-induced graphene (LIG) is produced rapidly by directly irradiating carbonaceous precursors, and it naturally exhibits as a three-dimensional porous structure. Due to advantages such as simple preparation, time-saving, environmental friendliness, low cost, and expanding categories of raw materials, LIG and its derivatives have achieved broad applications in sensors. This has been witnessed in various fields such as wearable devices, disease diagnosis, intelligent robots, and pollution detection. However, despite LIG sensors having demonstrated an excellent capability to monitor physical and chemical parameters, the systematic review of synthesis, sensing mechanisms, and applications of them combined with comparison against other preparation approaches of graphene is still lacking. Here, graphene-based sensors for physical, biological, and chemical detection are reviewed first, followed by the introduction of general preparation methods for the laser-induced method to yield graphene. The preparation and advantages of LIG, sensing mechanisms, and the properties of different types of emerging LIG-based sensors are comprehensively reviewed. Finally, possible solutions to the problems and challenges of preparing LIG and LIG-based sensors are proposed. This review may serve as a detailed reference to guide the development of LIG-based sensors that possess properties for future smart sensors in health care, environmental protection, and industrial production.

Infrared Laser‐Induced Graphene Sensor for Tyrosine Detection

“…In this sense, LIG electrodes on a flexible polyimide (PI) polymer have been highlighted as an affordable and single‐step protocol to obtain high‐quality graphene. This protocol can be performed at room temperature and without severe atmosphere control (it can be made in the presence of air) which is greatly valuable over previous procedures that require high‐temperature conditions or extremely oxidant media [20] . PI, commercially known as a Kapton, presents low‐cost, good surface‐to‐surface reproducibility, and high flexibility, which has been explored in the development of wearable sensors [21] .…”

“…This protocol can be performed at room temperature and without severe atmosphere control (it can be made in the presence of air) which is greatly valuable over previous procedures that require hightemperature conditions or extremely oxidant media. [20] PI, commercially known as a Kapton, presents low-cost, good surface-to-surface reproducibility, and high flexibility, which has been explored in the development of wearable sensors. [21] The obtaining of graphene is due to the photothermal conversion of sp 3 carbon of the polymeric matrix into sp 2 carbon.…”

Electrochemical Sensors Based on MoSx‐Functionalized Laser‐Induced Graphene for Real‐Time Monitoring of Phenazines Produced by Pseudomonas aeruginosa

“…A thin Nafion film is spin‐coated onto the electrode surface to protect the electrode from biofouling. [ 38 ] The inset shows the sensor bending, demonstrating the device's potential for flexible electronics and wearable devices, for example, for integration with strain sensors, [ 39 ] ECG patches, [ 40 ] or vital‐sign monitoring sensors. [ 41 ] A picture of the sensor attached to a testing connector and ready for testing is shown.…”

Recent Advances in Stretchable and Wearable Capacitive Electrophysiological Sensors for Long-Term Health Monitoring

“…Various printing processes and fabrication strategies [ 67 , 68 , 69 , 70 , 71 ] have also been developed to fabricate electrodes with good skin contact [ 72 ]. The electrodes of wearable sensors have been developed from various materials with good conductivity, such as carbon-based nanomaterials [ 73 ], including graphene [ 74 , 75 ], carbon nanotubes (CNTs) [ 76 ], carbon fibers [ 77 ], or metals such as gold [ 18 , 21 , 22 , 78 ] or metallic nanoparticles including nickel and silver [ 79 ]. Among them, CNTs have become promising candidates due to their good mechanical stability, excellent flexibility, and high conductivity [ 80 , 81 ].…”