Gas-sensing and electrical properties of perovskite structure p-type barium-substituted bismuth ferrite

Abstract

Schematic diagram of the proposed gas-sensing mechanism for the p-type BiFeO3 based gas sensor: (a) and (c) in air, (b) and (d) in reducing gas, (e) simplified equivalent circuit.

Enhanced visible-light activities of porous BiFeO3 by coupling with nanocrystalline TiO2 and mechanism

“…The estimated work function is 4.2 eV and its Fermi level is about 0.2 eV, which lies below the bottom of conduction band [7]. BiFeO 3 is a p-type semiconductor [33][34][35][36], whose band gap varies from 2.0 to 2.7 eV and its Fermi level lies close to its valance band. Here the band gap of BFO is calculated to be 2.07 eV according to the UV-vis DRS spectra.…”

Multiferroics beyond electric-field control of magnetism

“…(Bi,Sr)FeO 3 , with its high concentration of oxygen vacancies combined with high vacancy mobility, likely due to its large polarizability, shows promise for solid-oxide fuel cells [50]. A high Seebeck coefficient has been reported, suggesting possible thermoelectric relevance [51], as well as photostriction [52], photodetection [53], and gas sensing behavior [54,55]. Finally, resistive switching, with possible application in neuromorphic computing, has been reported [56].…”

Ag modified bismuth ferrite nanospheres as a chlorine gas sensor

“…Perovskite-type BFO nanospheres were synthesized by a sol-gel method as previously reported. 10,19,20 Briey, stoichiometric Bi(NO 3 ) 3 $5H 2 O and Fe(NO 3 ) 3 $9H 2 O were dissolved in CH 3 COOH and (CH 2 OH) 2 , respectively. The obtained solutions were mixed aer stirring for 30 minutes.…”

“…[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. 12,13 They are especially meaningful for detection of Cl 2 , but the researches about BFO in the eld of gas-sensing area are still limited due to its low sensitivity.…”