Effect of Pt/TiO2 interface on room temperature hydrogen sensing performance of memristor type Pt/TiO2/Pt structure

SENSORS AND ACTUATORS B-CHEMICAL

卷:253

Article

Haidry, Azhar Ali^1,2  Ebach-Stahl, Andrea¹  Saruhan, Bilge¹ 

[1] German Aerosp Ctr DLR, Inst Mat Res, D-51147 Cologne, Germany

[2] Nanjing Univ Aeronaut & Astronaut, Coll Mat Sci & Technol MST, JiangJun Ave 29, Nanjing 21101, Jiangsu, Peoples R China

关键词: Hydrogen sensors;    Pt/TiO2/Pt;    Memristor;    Metal/Semiconductor interface;    Conducting filaments;   

DOI  :  10.1016/j.snb.2017.06.159

来源: Elsevier

【 摘 要 】

In this paper, a sensor with memristor electrode geometry (Pt/TiO2/Pt) was fabricated by a simple and cost-effective method yielding 10(6) orders of resistance change with short reaction times (T-res similar to 19 and T-rec similar to 118 s) when exposed to 1 vol.% H-2. Under wet conditions an increase in sensor response toward 1 vol.% H-2 independent of operating temperature RT-100 degrees C (T-res similar to 5 s) and a reasonable H-2-selectivitywas observed in the presence of CO and NO2. Such sensor characteristics with lower power consumption offer great advantages and are highly suitable for fuel cell and hydrogen safety applications. Despite the knowledge that hydrogen atoms accumulate at Pt/TiO2 interface reducing Schottky barrier height( i.e. decreasing the resistance of the Pt/TiO2 interface by several orders of magnitude) the details of the involved sensing mechanisms, especially under humidity, is still incomplete. The results confirm the existence of both electronic and ionic conductivity within TiO2 sensing layer and their significant alteration under hydrogen exposure. Thus a sensing model is proposed that fit exceptionally well with the memristor-type resistance variation principle. The understanding gained by the proposed model will allow the fabrication of innovative sensors for stable, selective and robust H-2 detection. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

Free