Preparation Of Ultra-sensititive And Highly Specific Miniature Hydrogen Gas Sensor Based On Insitu Synthesis Method

Hydrogen gas sensor is an important safety monitoring device in chemical production.Low-cost,low-power,highly sensitive micro hydrogen gas sensors have important practical value.This research work is based on the in situ synthesis of micro-heating plates to obtain a gold-doped tin dioxide（SnO₂）nanostructured ultra-sensitive and highly specific micro-nano sensor.The location of an array of ordered polystyrene microspheres（Polystyrene Spheres,spheres）,which can be used as a sacrificial growth of metal oxides by homogeneous chemical precipitation,was achieved through a self-assembled selective microheated chip surface modification using an in situ synthesis method to form oxide metal thin films on the surface of the templates,the method ensures control of the morphology and placement of the sensing material only in the active heating region of the microheating platform.It is shown that the micro-nano sensor has a sensitivity of up to 100 for hydrogen at 50 ppm concentration and a response of only 4.5 for the important interfering gas alcohol at the same concentration conditions,producing a significant suppression effect for carbon monoxide and methane at the same concentration conditions.In addition,the micro-nano sensor is also stable,maintaining good stability measurements for 35 days.XPS characterization shows that the proportion of defective oxygen in the material is the main reason for the super-sensitivity of the sensor,and the larger the proportion of defective oxygen in the material,the more beneficial to improve the sensing performance of the material.Also the in situ preparation method can be flexible and scalable for the preparation of high-performance miniaturized gas sensors with various hollow sphere nanostructured metal oxides for superior sensitivity and tunable selectivity.