Abstract
A resistivity-type hydrogen (H-2) sensor based on palladium (Pd)-decorated zinc oxide (ZnO) nanorod (NR) array has been developed to detect the dissolved H-2 gas in the transformer oil. The Pd catalyst decorated on the ZnO NRs not only enhanced the H-2 sensing properties at room temperature, but also played an important role to protect the ZnO NRs in liquid environment, which resulted long-term stability of the fabricated device. The H-2 sensor had a temperature coefficient of resistance (TCR) of 68.45 x 10(-4)/degrees C, and showed the potential to detect H-2 gas dissolved in transformer oil with a detection range of 5-1000 ppm. The sensor showed high response towards H-2 within 5-100 ppm gas concentrations, which is critical to develop a H-2 sensor for transformer oil. The kinetic H-2 absorption/desorption in sensors was also investigated at different oil temperatures. Moreover, the fabricated sensor achieved high response, good repeatability, and long-term stability in oil, making it a promising candidate for transformer oil applications. (C) 2015 Elsevier B.V. All rights reserved.