A gas sensor includes a housing having disposed therein a membrane electrode assembly comprising a sensing electrode, a counter electrode, and a polymer membrane disposed between the sensing electrode and the counter electrode. The polymer membrane comprises an ionic liquid retained therein. The sensor also includes a catalyst support that can be stable in a range of potentials to allow for detection mode and catalyst regeneration mode to be operative. The sensor further includes a circuitry and algorithm to implement the catalyst regeneration mechanism electrochemically. The sensor further includes a chamber for reference gas to which the counter electrode is exposed, and a chamber for test gas to which a gas to be tested is exposed. The sensor also includes a pathway for test gas to enter the chamber and a measured electrical circuit connecting the sensing electrode and the counter electrode.