Magneto-Semiconductor Resistor for Hydrogen Detection

The fabrication and testing of hierarchical architecture based Zinc Ferrite-Zinc oxide (ZnFe
₂
O
₄
-ZnO) magnetic semiconductor (MS) sensor, for the detection of Hydrogen (H
₂
) down to 50 parts per million (ppm) at room temperature, are reported in this study. The synthesis of ZnFe
₂
O
₄
-ZnO heterostructure has been carried out using a simple hydrothermal route. The MS sensor shows good sensitivity, quick response, and remarkably good recovery to H
₂
at room temperature. A rise in the magnetic movement is verified in ZnFe
₂
O
₄
-ZnO heterostructure with the interaction of reducing H
₂
gas. The sensor exhibits a detection limit of 8.9 ppm with the highest sensitivity of 20% for the detection of 900 ppm of H
₂
, with a response time of 35-55 s. The sensitivity of the MS sensor towards some of the breath volatile organic compounds (VOCs) and cross-sensitivity of H
₂
and carbon dioxide (CO
₂
) are analysed. The work is aimed to provide a straightforward approach for the H
₂
breath test using magnetic particles that have the potential to become a portable device for diagnostics.