Description:
<jats:title>Abstract</jats:title><jats:p>The α‐Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> porous array film is synthesized based on an alternative and flexible route by transferring a solution‐dipped self‐organized colloidal template onto device substrate and subsequent annealing treatment. The sensing properties of the film to H<jats:sub>2</jats:sub>S and other interfering gases were studied in detail. It was observed that porous array film annealed at 400 <jats:sup>o</jats:sup>C showed optimized sensing performance with both higher response and better selectivity to H<jats:sub>2</jats:sub>S than those annealed at 300 <jats:sup>o</jats:sup>C, 500 <jats:sup>o</jats:sup>C and 600 <jats:sup>o</jats:sup>C. Detailed researches indicated the grain size of the α‐Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> porous array film was closely related to annealing temperature, in which the sensing properties to H<jats:sub>2</jats:sub>S was deeply affected by the crystallization effect. A possible gas sensing mechanism was thus proposed. Generally, the higher crystallinity leads to better selectivity while large grain size will decrease response. This work gives an alternative way to realize H<jats:sub>2</jats:sub>S detection with high response and selectivity.</jats:p>