Highly sensitive triethylamine gas sensor based on CeO₂-modified Au–ZnO

The paper adopted a two-step hydrothermal method to fabricate CeO₂-modified Au–ZnO (CAZ) nanosheets, as well as investigated the gas-sensing performance of CAZ composites and Au–ZnO materials with various CeO₂ contents to triethylamine. It has been found that the sensitivity of the 0.5% CAZ composite material (382) is enhanced by a factor of 4.2 over the Au/ZnO material at 220 °C. The response time is accelerated from 4 to 3 s, while it also possesses outstanding selectivity and stability. The outstanding gas-sensitizing performance is attributable to the catalytic and overflow effects of Au as well as the n–n heterojunction constructed among CeO₂ and ZnO, which provides additional carriers for the material to adsorb more oxygen and triethylamine molecules.