Patent ID: 8613843

Claim:
An electro-chemical sensor for measuring methane in situ, comprising: a first electrode coupled with a plurality of activation centers, the plurality of activation centers comprising a catalyst that at least partially oxidizes methane under standard conditions for a redox reaction producing reaction products including methanol, wherein the first electrode is in discrete contact with the reaction products and the catalyst comprises one of an iron, copper or transition metal compound, and wherein the plurality of activation center comprises the catalyst surrounded by a membrane comprising aliphatic molecules having a lower end comprising saturated hydrocarbon chains of up to 18 carbon atoms in the backbone structure and an upper end comprising polyethylene glycol chains and the lower end of the aliphatic molecules are coupled to the first electrode; a second electrode in discrete contact with the reaction products; a third electrode configured to be held at a fixed potential and generate a stream of dioxygen bubbles by hydrolyzing water; and an electronic circuit electrically coupled with the first and the second electrodes and configured to measure an oxidation current resulting from the partial oxidation of the methane into methanol, wherein a magnitude of the oxidation current is proportional to a concentration of the methane.