Origin of irreversible to reversible transition in acetone detection for Y-doped BiFeO3 perovskite

To eliminate the demerits of irreversibility associated with a gas-sensing material, it is always indispensable to know the exact origin of the same. In this view, the present study associates a perovskite to investigate the origin of irreversible sensing by a non-conventional bismuth ferrite (BiFeO3) nanomaterial prepared by a simple solgel technique. Yttrium (Y) doping in BiFeO3 significantly enhances the response performance and eliminates the irreversible nature, showing a reversible-type sensing behavior for selective detection of acetone (cross selectivity, R-cross=R-Acetone/R-xylene: 20) along with the virtue of very low sensing ability (1ppm), long-term stability with a negligible deviation in response value (R=3.5 +/- 0.25) toward 5ppm acetone tested repeatedly for 300 days, and excellent repeatable over nine loops character desirable for practical application of the perovskite material. A remarkably highest response (R=Delta G/G(a)) of 52 was achieved toward acetone utilizing Y-doped BiFeO3 perovskite. A possibility of the formation of closed pores and incomplete desorption of the reducing species (volatile organic compounds) from the active sites of the sensor has been considered the prime origin of unfinished recovery. Finally, irreversible to reversible transition in sensing has correlated with the structural and morphological change resulting from the substitution of the Bi3+ ion by the Y3+ ion, particularly at the A-site of the perovskite BiFeO3 due to Y-doping.