N-doping effects on the oxygen sensing of TiO2 films

C. BUONO; P.M. DESIMONE; F. SCHIPANI; C.M. ALDAO; C.I. VIGNATTI; C.I.N. MORGADE; G.F. CABEZA; T.F. GARETTO

JOURNAL OF ELECTROCERAMICS

SPRINGER

Lugar: Berlin; Año: 2018 vol. 40 p. 72 - 77

1385-3449

Gas sensors based on Titanium dioxide films havebeen a subject of interest due to its high sensitivity and lowcost. The sensing mechanism of this type of sensors is basedon the conduction mechanism, which is governed by the potentialbarriers formed at the inter-grains of the polycrystallinestructure. The shape of these potential barriers strongly dependson the characteristics of the material, and then it isexpected that a doping aggregation will affect significantlythe conductivity and thus the sensitivity of the sensor. In thiswork, we study the effect in the oxygen sensitivity of titaniumdioxide films due to N-doping.We developed a model in orderto explain our experimental results based on the fact that, forthe particle size of our titanium dioxide samples, grains arecompletely depleted of carriers.