Selective Hydrogen Sensing Using Fe₂O₃/TiO₂ Nanocomposites

These Nanocomposites based on α-Fe₂O₃/TiO₂ nanocomposite were hydrothermally synthesized and characterized. A sensor device incorporating the nanocomposite was fabricated to assess its hydrogen (H₂) gas sensing performance. Amongst the composites, Fe₂O₃/TiO₂ (10:1) showed the highest sensing signal (S) of 109.8, response with response time (T₉₀) 295 s, and the recovery time (Tr₉₀) 97 s for the H₂ concentration of 1000 ppm. When different concentrations of H₂ gas (15, 50, 100, and 1000 ppm) were used, the quick response time was obtained at 15 ppm H₂ concentration. For the interference study, a mixed gas composition of H₂ (100 ppm), NO₂ (10 ppm), CH₄ (100 ppm), and CO (100 ppm) was used to study the selectivity. The Fe₂O₃/TiO₂ (10:1) composite was found to have clear selectivity with a sharp sensing signal of 48.24, which was much higher than the rest of the signals.