Direct and Reagent‐Free Fabrication of a Laser‐Induced‐Graphene‐Gold Nanocomposite Electrode From Gold Leaves Using a Do‐It‐Yourself Blue Laser System

This study proposed a new method for the direct and reagent‐free fabrication of laser‐induced graphene (LIG)‐gold (Au–LIG) nanocomposite electrodes on a polyimide (PI) film using a commercially available, low‐cost do‐it‐yourself (DIY) blue laser system for the first time. The one‐step fabrication of Au–LIG nanocomposite was achieved by simply irradiating a PI film previously covered with gold leaves using a blue laser. Surface analysis and electrochemical oxidation of glucose revealed the formation of Au–LIG nanocomposites on the electrodes. Electrochemical sensitivity of the Au–LIG electrode against glucose in the concentration range from 0.1 to 50 mM was 153.4 µA/cm 2 /mM‐glucose, and its limit of detection was 45.5 µM. This simple and cost‐effective DIY blue laser system is expected to significantly contribute to the low‐cost mass production of high‐performance chemical sensors.