Hierarchical Assembly of α-Fe2O3 Nanorods on SnO2 Nanosheet Arrays for Acetone Detection at Sub-ppm Level

We report for the first time an acetone sensor based on novel SnO
₂
/α-Fe
₂
O
₃
hybrid nanoarrays (HNAs), which may be used in breath acetone analysis. The SnO
₂
/α-Fe
₂
O
₃
HNAs are synthesized through a cost-effective two-step liquid-phase process at low temperature. By applying an on-chip synthesis method, α-Fe
₂
O
₃
nanorods are grown on the prefabricated SnO
₂
nanosheet arrays (NSAs). Gas-sensing properties of the SnO
₂
/α-Fe
₂
O
₃
HNAs based sensor are investigated, which shows a greatly improved response to acetone (2.3, at 0.4 ppm) at sub-ppm level compared to pure SnO
₂
NSAs (1.2, at 0.4 ppm). The SnO
₂
/α-Fe
₂
O
₃
HNAs based sensor also presents good selectivity and reproducibility to acetone, indicating its potential in practical application.