Abstract: A gas sensor element includes a solid electrolyte having oxygen-ion conductivity, a first electrode film located on one side of the solid electrolyte, a second electrode film located on the other side of the solid electrolyte. At least one of the first electrode film and the second electrode film includes noble metal particles, solid electrolyte particles having oxygen-ion conductivity, and pores, and a capacitance in the electrode film is 80 ?F or less. A gas sensor includes the gas sensor element.

Abstract: A gas sensor element includes a solid electrolyte body having oxygen ion conductivity, a measurement electrode provided on one surface of the solid electrolyte body and exposed to a measurement gas, and a reference electrode provided on the other surface of the solid electrolyte body and exposed to a reference gas. Both the measurement electrode and the reference electrode include noble metal particles, solid electrolyte particles having oxygen ion conductivity, and pores. The measurement electrode comprises a surface measurement electrode layer comprising a surface serving as a contact surface with the measurement gas and an intermediate measurement electrode layer disposed in contact with a surface at solid electrolyte body side of the surface measurement electrode layer. The surface measurement electrode layer has a higher porosity than the intermediate measurement electrode layer has. The gas sensor comprises the gas sensor element.

Abstract: A gas sensor element includes a solid electrolyte having oxygen-ion conductivity, a first electrode film located on one side of the solid electrolyte, a second electrode film located on the other side of the solid electrolyte. At least one of the first electrode film and the second electrode film includes noble metal particles, solid electrolyte particles having oxygen-ion conductivity, and pores, and a capacitance in the electrode film is 80 ?F or less. A gas sensor includes the gas sensor element.