Sodium Titanate Nanorod Moisture Sensor and Its Sensing Mechanism

Author

Yupeng Zhang ; Ying Zhang ; Bo Fu ; Wei Li ; Wenbin Guo ; Shengping Ruan ; Dali Liu ; Yu Chen

Author_Institution

State Key Lab. on Integrated Optoelectron., Jilin Univ., Changchun, China

Volume

34

Issue

11

fYear

2013

fDate

Nov. 2013

Firstpage

1424

Lastpage

1426

Abstract

Sodium titanate Na₂Ti₆O₁₃ nanorods were synthesized by a hydrothermal method and characterized by X-ray diffraction and scanning electron microscopy. Then, the material was coated on a Al₂O₃ ceramic substrate to fabricate humidity sensors using Ag-Pd as interdigitated electrodes. The sensor shows high humidity sensitivity and fast response and recovery. The impedance changes by five orders of magnitude over a relative humidity (RH) range from 11% to 95%. At the frequency of 100 Hz, response and recovery times are both <;2 s, and the maximum hysteresis is <;3% RH. In addition, the complex impedance at different RH was investigated to understand the sensing mechanism. The results indicate potential applications of sodium titanate for fabricating high-performance humidity sensors.

Keywords

X-ray diffraction; electrodes; humidity sensors; moisture; nanofabrication; nanorods; palladium; scanning electron microscopy; silver; Ag-Pd; Al₂O₃; Na₂Ti₆O₁₃; X-ray diffraction; ceramic substrate; complex impedance; fast response and recovery; frequency 100 Hz; humidity sensitivity; humidity sensors; hydrothermal method; hysteresis; interdigitated electrodes; moisture sensor; relative humidity; scanning electron microscopy; sensing mechanism; sodium titanate nanorod; Humidity; Impedance; Materials; Nanowires; Sensors; Titanium compounds; Complex impedance; humidity sensor; response and recovery; sodium titanate;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2013.2282832

Filename

6634201