Ultrasonic-triggered Surface Morphological Reconstruction of MoS2 for Enhanced Ultrasensitive Humidity Sensing

Defects on a surface can improve response activities in a humidity sensor. A novel preparation process of sonication-triggered morphological evolution of additional defect was reported in this work. Herein, an ultra-responsive humidity sensor prepared by defect-rich MoS2 nanospheres has been demonstrated. The morphology, element distribution and the abundant defects of MoS2 NSs were characterized by SEM, TEM, EDS, XRD, Raman and XPS. There are many defects which act as active adsorption sites on the surface of MoS2 NSs. Profiting by surface defects and fast charge transfer, the defect-rich MoS2 NSs delivered remarkably ultrasensitive humidity sensing with a response as high as 5560 and ultrafast response-recovery behaviors, and excellent repeatability. Moreover, the humidity sensing mechanism of the sensor was discussed summarily.

Automated summary

This study reports a novel preparation process of defect-rich MoS2 nanospheres through sonication-triggered morphological evolution, leading to the construction of an ultra-responsive humidity sensor. The defect-rich MoS2 nanospheres exhibit remarkably high response values, ultrafast response-recovery behaviors, and excellent repeatability, benefiting from surface defects and rapid charge transfer. The humidity sensing mechanism of the sensor was briefly discussed.