Nanopatterning-Enhanced Sensitivity and Response Time of Dynamic Palladium/Cobalt/Palladium Hydrogen Gas Sensors

Clear advantages of nanopatterned Pd/Co films over continuous Pd/Co films are demonstrated as candidates for future hydrogen gas sensing devices based upon hydrogen-absorption-modified ferromagnetic resonance. Nanopatterning results in a higher sensitivity to hydrogen gas and a much faster hydrogen desorption rate. It also avoids the need for an external biasing magnetic field which may be important for practical sensor implementation. A wide range of hydrogen gas concentrations has been detected with the nanopatterned material: from 0.1% to 50%, across the threshold of hydrogen flammability in air (4%).