Highly Robust Double Memristive Device Based on Perovskite/Molybdenum Oxide‐Sulfide Compound Heterojunction System

Halide organic–inorganic perovskites (HOIPs) are a promising class of materials for neuromorphic computing and processing systems demonstrating a variety of resistive switching (RS) mechanisms. HOIPs have been used as active layers in two‐ and three‐terminal synaptic devices reporting high performance in metrics of speed and energy consumption. Nevertheless, halide perovskites suffer from poor ambient stability and reproducibility. In this work, a highly robust double memristor based on two active layers forming a stacking heterojunction is demonstrated. In particular, the functional layer consists of a molybdenum oxide‐molybdenum sulfide compound (MoO3‐MoS2) and a quadruple cation perovskite (RbCsMAFA) deposited on top showing favorable band alignment for the specific application. The double memristor based on the MoO3‐MoS2/RbCsMAFA heterojunction exhibits impressive and stable resistive switching behavior with endurance of 100 cycles, high retention of 2 × 104 s, high environmental stability maintaining its memristive behavior for 1 month, and excellent artificial synaptic functions. The robust device also exhibits good thermal stability maintaining the memristive characteristics at 85 °C, as well as good photonic memristive behavior with an improved ON/OFF ratio under constant illumination. Here it is proven that the proposed double memristor is a promising candidate for artificial synapses and neuromorphic computing systems.