We report a sputtered PdO decorated TiO2 sensing layer by radiofrequency (RF) sputtering methods and demonstrated gas sensing performance for H2 gas. We prepared sputtered anatase TiO2 sensing films with 200 nm thickness and deposited a Pd layer on top of the TiO2 films with a thickness ranging from 3 nm to 13 nm. Using an in situ TiO2/Pd multilayer annealing process at 550°C for 1 hour, we observed that Pd turns into PdO by Auger electron spectroscopy (AES) depth profile and confirmed decorated PdO on TiO2 sensing layer from scanning electron microscope (SEM) and atomic-force microscope (AFM). We also observed a positive sensing signal for 3, 4.5, and 6.5 nm PdO decorated TiO2 sensor while we observed negative output signal for a 13.5 nm PdO decorated one. Using a microheater platform, we acquired fast response time as 11 sec and sensitivity as 6 μV/ppm for 3 nm PdO under 33 mW power.
Bibliographical noteFunding Information:
This work was supported by a National Research Foundation of Korea grant funded by the Korean government (MEST; NRF-2015R1D1A1A01059806) and by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health and Welfare, Republic of Korea (Grant no. HI16C0272). The work reported in this paper was conducted during the sabbatical year of Kwangwoon University in 2015.
All Science Journal Classification (ASJC) codes
- Materials Science(all)