KIT-5-Assisted Synthesis of Mesoporous SnO₂ for High-Performance Humidity Sensors with a Swift Response/Recovery...

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Semiconductor metal oxide (SMOX) sensors face challenges in sensitivity and response time for humidity sensing.
• Controlling material morphology is key to improving water-vapor adsorption/desorption dynamics.

Purpose of the Study:

• To develop a highly efficient SMOX sensor with enhanced humidity sensing capabilities.
• To investigate the effect of controlled pore morphology on sensor performance.

Main Methods:

• KIT-5-mediated synthesis to create mesoporous tin(IV) oxide replica (SnO2-R).
• Comparison with sol-gel synthesized tin(IV) oxide (SnO2-SG).
• Characterization using TEM, BET, SWAXS, and XPS.

Main Results:

• SnO2-R exhibited a high specific surface area and open pore structure, unlike SnO2-SG.
• SnO2-R demonstrated excellent room-temperature humidity sensing with low hysteresis (3.7%), high sensitivity (406.8 kΩ/RH%), and fast response/recovery (4 s/6 s).
• Increased oxygen-related defects were observed on the SnO2-R surface.

Conclusions:

• The controlled mesoporous structure and defects of SnO2-R significantly enhance humidity sensing performance.
• SnO2-R is a promising material for real-time, high-performance humidity sensors.