High‐Performance Electrochemical Sensors Based on Laser‐Irradiated Carbon Nanotube Electrodes for Detection of Hydrogen Peroxide

The development of electrochemical sensors (ECSs) with enhanced sensitivity has emerged as a focal point in contemporary sensor technology research due to the important biochemical roles of hydrogen peroxide (H 2 O 2 ) in the industrial and biological fields. In this paper, a high‐performance ECS based on laser‐irradiated carbon nanotube (LICNT) electrode as the working electrode (ECS‐LICNT) for sensitive detection of H 2 O 2 is designed and fabricated to achieve long‐term monitoring of trace concentrations of H 2 O 2 . The thickness and surface microcluster structure of LICNT electrodes were optimized by precise control of laser energy density and CNT suspension dose. The ECS‐LICNT, designed with a dual mechanism combining surface laser‐induced oxidation to increase active point density and ordered microcluster structure to enhance effective active area, possesses a high sensitivity of 475 μA·mM −1 ·cm −2 in a wide range (10–9000 μM), surpassing most reported pure carbon‐based sensors. In addition, the sensor exhibits excellent stability (current decay <5% within 7200 s) and reproducibility (RSD = 2.3%, n = 7), maintaining 95.8% of its initial response even after 28 days of storage. The ECS demonstrates sufficient sensitivity to accurately determine H 2 O 2 concentration in the presence of interfering substances such as ascorbic acid (AA), glucose (Glu), and uric acid (UA). It can be foreseen that this sensor provides a novel strategy for designing efficient ECSs and has broad application prospects in the fields of biomedicine and food safety detection.