Annealing Effects on SnO 2 Thin Film for H 2 Gas Sensing.

Hydrogen (H 2 ) is attracting attention as a renewable energy source in various fields. However, H 2 has a potential danger that it can easily cause a backfire or explosion owing to minor external factors. Therefore, H 2 gas monitoring is significant, particularly near the lower explosive limit. Herein, tin dioxide (SnO 2 ) thin films were annealed at different times. The as-obtained thin films were used as sensing materials for H 2 gas. Here, the performance of the SnO 2 thin film sensor was studied to understand the effect of annealing and operating temperature conditions of gas sensors to further improve their performance. The gas sensing properties exhibited by the 3-h annealed SnO 2 thin film showed the highest response compared to the unannealed SnO 2 thin film by approximately 1.5 times. The as-deposited SnO 2 thin film showed a high response and fast response time to 5% H 2 gas at 300 °C of 257.34% and 3 s, respectively.