In this Letter, we present a dual-layer oxide volatile memristor characterized by an Ag/TaOx/ZnO/Pt structure. This innovative design deviates from traditional Ag/ZnO/Pt devices, chiefly through the introduction of a thin TaOx layer between the electrolyte and the active electrode. Our devices exhibit remarkable features, including an unprecedentedly low switching voltage slope, measuring a mere 0.221 mV/dec, and a threshold voltage that can be reduced to as low as 0.177 V. To further elucidate the performance enhancement of the device, we utilize first-principles calculations. The results reveal that the relatively high formation energy of oxygen vacancies in the supplementary TaOx layer facilitates meticulous control over the rupture and formation of silver conductive nanofilaments.