Power reduction with enhanced sensitivity for pellistor methane sensor by improved thermal insulation packaging

The pellistor (catalytic combustion) methane sensor is a typical sensor with high working temperature. Historically, its heat dissipation via packaging has not been fully considered for power minimization. A large amount of thermal energy from the pellistor sensor is typically lost to the environment because of the sensor's high sensing temperature and quasi-closed metal packaging. A promising new approach to minimize the sensor power budget will be developed when part of this heat energy is successfully retained. In this paper, we explore this possibility by introducing hydrophobic silica aerogel as packaging material owing to its excellent low thermal conductivity and high gas permeability. Experimental results reveal that a significant power decrease of approximately 30% and high sensitivity can be simultaneously achieved for the traditional active pellistor methane sensor with thermal insulation-strengthened packaging with silica aerogel. (C) 2012 Elsevier B. V. All rights reserved.