Semiconducting properties of Ge-doped BaSnO3 ceramic

Abstract

a b s t r a c tThe electrical and optical properties of Ge-doped BaSnO 3 ceramics sintered at various temperatures have been investigated to determine their semiconductor behavior. The electrical conductivity of Gedoped BaSnO 3 samples increases with increase in temperature, confirming that the samples exhibit a semiconductor behavior. A maximum conductivity value of 6.31 × 10 −9 S/cm was observed for the sample sintered at 1200 • C. The optical band gaps of the Ge-doped BaSnO 3 samples were determined by means of reflectance spectra. The variation of optical band gap with temperature was analyzed using E g (T) = E go +ˇT relation. The rate of change of the band gapˇof BaSn 0.99 Ge 0.01 O 3 was found to be 7.6 × 10 −4 (eV/ • C). A minimum optical band gap value of 2.95 eV was observed for the sample sintered at 1400 • C. It is evaluated that BaSn 0.99 Ge 0.01 O 3 is a wide band gap semiconductor and its semiconducting properties change with sintering temperature.

Structural and optical characterization of BaSnO3 nanopowder synthesized through a novel combustion technique

“…This experimentally obtained band gap is found to be lower than the standard one [36]. The obtained value is similar as that obtained by Koferstein and Yakuphanoglu [37] which they reported for germanium doped BaSnO 3 . Such a change in band gap can be partially attributed to the quantum size effects, i.e.…”

Nanocrystalline BaSnO3 as an Alternative Gas Sensor Material: Surface Reactivity and High Sensitivity to SO2

“…Two regions of conductance with different activation energy values could be outlined from the linear lgσ-1/T dependences (Figure 4a): the lower-temperature one at 150–300 °C and the higher-temperature one at 350–450 °C. Such an effect at close threshold temperature but with different activation energy values was observed in other studies by DC-conduction as well as impedance measurements [16,22]. The lower-temperature activation energy has low value of E A,l = 0.14–0.15 eV and is independent on annealing temperature of the samples (Figure 4b).…”

“…Valence band is mainly consisted of nonbonding O 2 p orbitals [20,21]. The band gap was found to increase due to partial substitution of Sn by Sb [14]; increasing the calcination temperature of the materials resulted in narrowing the band gap [22]. The synthesis of BaSnO 3 is complicated by the need of hard reaction conditions for the formation of perovskite structure.…”

Preparation and characterization of nano structured Ba2SnO4 as a novel photocatalyst material for the chromate reduction

“…The WHO has drastically limited the Cr(VI) concentration in water at 0.5 ppm and the effluents must be treated at the source. On the other hand, a great interest has been paid to the elaboration of optically active materials, the key element in photocatalysis (Köferstein and Yakuphanoglu 2010;Noori et al 2012). Oxides are privileged for photo-electrochemical (PEC) applications because of their chemical stability.…”