“…It was reported that BFO exhibited excellent gas-sensing properties. [7][8][9] Perovskite BFO, as p-type oxide semiconductors, displays more stable and reliable gas-sensing properties than binary metal oxides, such as ZnO, CuO and SnO 2 , resulting from the fact that the ternary oxides consists of two differently sized cations. 10,11 At the same time, BFO possesses distinctive surface reactivity, oxygen adsorption and relatively narrow band gap (2.19 eV) which are advantageous for enhancing gas selectivity, decreasing the humidity dependence of sensor signals to negligible levels, being conducive to transportation of valence electrons and improving recovery speed.…”