Custom designed metal anchored SnO2 sensor for H2 detection

Herein, we report sputter deposited SnO2 thin film based sensor structures anchored with different metal clusters (Pt, Au, Cu, In, W and Cr) for efficient detection of H2 gas. Controlled decoration of ∼9 nm thin Pt clusters having 200 μm dia on the top surface of SnO2 thin film exhibited dramatically outperformed results. The Pt/SnO2 sensor shows an improvement upto two orders in sensing response S∼1.68 × 102 towards 500 ppm of H2 gas at a relatively low operating temperature of 110 °C. The sensor exhibited excellent gas sensing characteristics in the concentration range 2-5000 ppm H2 at operating temperatures of 70-230 °C. The sensor revealed negligible cross sensing signals against other interfering gases like acetone, IPA, TCE, NO2, methane, LPG, petrol and NH3. The structural and surface morphological studies of SnO2 thin films were carried out. Reliability analysis and selectivity demonstration by Pt/SnO2 sensor was found to be consistent over long term. The work envisions towards realization of targeted H2 detection system at low temperature.