High performance humidity sensor based on 3-D mesoporous SnO₂ derived via nanocasting technique

This research explores humidity sensing of 3-D mesoporous SnO₂, presenting a novel approach for addressing the growing demand for advanced nanomaterials in environmental monitoring and remediation. We examined the variations in electrical resistance of mesoporous SnO₂ in response to different humidity levels. Mesoporous SnO₂ was made using MCM-48 as a hard template by nanocasting method and analysed using suitable techniques. The finding indicates the successful replication of the cubic mesoporous structure of MCM-48 using SnO₂. The SnO₂ replica maintains the unique three-dimensional cubic arrangement and the high specific surface area characteristic of MCM-48, with a measured surface area of 823.45 m²/g. Mesoporous SnO₂ humidity sensors exhibit remarkable sensitivity (1180.229 Ω/RH%) attributed to the altered resistance under variety of humidity conditions, which improves the accuracy of moisture measurement. Notably, the sensor shows a linear declination of resistance towards mid-range of relative humidity, indicating high sensitivity. The sensor exhibits a significant resistance shift of 4.5 orders, with a rapid response time of 8.2s and a recovery time of 9.5s. This study emphasizes the versatility of mesoporous SnO₂ and highlights its potential to address current challenges in humidity sensing.