Thermal conductivity detector based gas sensor and associated method

A sensing device comprising:

• a substrate;
• a conducting element positioned on the substrate, the conducting element comprising first and second dissimilar materials arranged such that there is a first junction between the first and second dissimilar materials and a second junction between the first and second dissimilar materials, the conducting element further comprising first and second connection terminals;
• a direct current (DC) voltage source;
• a voltage measuring device;
• a first switching circuitry for selectively connecting the DC voltage source to the first and second connection terminals of the conducting element;
• and,
• a processor that controls the first switching circuitry to selectively connect the DC voltage source to the first and second connection terminals of the conducting element to apply a DC voltage across the first and second connection terminals of the conducting element for a first period of time and to selectively disconnect the DC voltage source from to the first and second connection terminals of the conducting element to measure a voltage across the first and second connection terminals over a second period of time.