New optical hydrogen sensor with fast response time based on multilayer palladium-nickel-PTFE thin film for explosion-proof detection of high H2 concentrations of 1-100%

Hydrogen detection is of great interest in many fields such as hydrogen concentrations around the explosive limit of 4% or in areas where strong electrical fields are present. Optical sensors have the advantage that they are not affected by these conditions. A comparison of three thin film sensors made of Pd, Pd Ni and Pd Ni / PTFE to detect H-2 is made. The double-sided samples are purpose built by plasma sputtering, with a thickness of 4nm on each side. It is shown that the signal of a pure Pd deposit is strong but it cannot resist higher H-2 concentrations. The Pd Ni deposit has shown good results and is able to resolve even higher concentrations of 10% H-2 but cannot resist high concentrations of H2 over many cycles. The new Pd Ni / PTFE deposit can be used many times for concentrations up to 100% without any damage and can detect concentrations of 1-100% of H-2. Furthermore the response time for deposits of different thickness is tested.