Conduction mechanisms in SnO2 single-nanowire gas sensors: An impedance spectroscopy study

F. SCHIPANI; D.R. MILLER; M.A. PONCE; C.M. ALDAO; S.A. AKBAR; P.A. MORRIS; J.C. XU

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2017 vol. 241 p. 99 - 108

0925-4005

Results of studies on single and multiple SnO2nanowire gas sensors with impedance spectroscopy arereported. Equivalent circuit modeling is used to draw fundamental conclusions about the dominant con-duction mechanism in single-nanowire sensors, where the diameter of the nanowire is found to play akey role. This is then extended to multiple-nanowire sensors. For single-nanowire sensors, I?V measure-ments are also used to demonstrate that the contribution from the electrode-nanowire contact to theoverall resistance changes with atmosphere and temperature. We find that for the randomly-orientatedmultiple-nanowire sensors, the main contribution to the resistance comes from the nanowire?nanowirejunction.