Development and Optimization of an Algorithm for Accurate Estimation of Real-Time Hydrogen Concentration Using a ZnO-Based Gas Sensor

Author(s): Jitthu Joseph [sup.1] , G. Uma [sup.2] , M. Umapathy [sup.2] , C. S. Prajapati [sup.3] , M. Manjunatha Nayak [sup.1] Author Affiliations: (1) grid.34980.36, 0000 0001 0482 5067, [...]
This paper addresses the problem of estimation of hydrogen gas concentration using current output from a sensor chip, integrated with a thin film of ZnO as a sensing layer and inbuilt microheater to obtain desired operating temperature by proposing an appropriate algorithm. The proposed algorithm minimizes the estimation delay while maximizing the estimation accuracy. The proposed algorithm also accounts for the variation in sensor performance with relative humidity. The key features of the proposed algorithm are low computational complexity, low memory requirements, compatibility with any metal-oxides-based hydrogen sensors with independent calibration or turning points, and minimal requirements to the calibration time. As proof of concept, a demonstration of the algorithm efficiency is evaluated by estimating hydrogen concentration using ZnO thin film-based gas sensor device and comparing its performance with available state-of-the-art hydrogen sensor algorithm outputs.