E-Synapse Based on Lead-Free Organic Halide Perovskite (CH3NH3)3Sb2Cl9 for Neuromorphic Computing

Memristors based on organic-inorganic halide perovskite have received intensive attention because of its solution-processability and defect-tolerant characteristics. But the lead element in perovskite is inevitably harmful to human body and environment. Herein, we report an e-synapse based on lead-free organic halide perovskite (CH
₃
NH
₃
)
₃
Sb
₂
Cl
₉
(MA
₃
Sb
₂
Cl
₉
), which exhibits excellent mimic of biological synaptic characteristics, such as excitatory postsynaptic currents (EPSCs), inhibitory postsynaptic currents (IPSCs), and paired-pulse facilitation (PPF). Furthermore, the synaptic weight of the e-synapse is found to be dependent on the frequency of pulse stimulation. The charge conduction mechanism of the e-synapse is proposed based on the in-depth investigation of the electrical characteristics of the devices. This work demonstrates that lead-free organic perovskite MA
₃
Sb
₂
Cl
₉
provide a new perspective on engineering e-synapses for neuromorphic computing and have a great potential for environment-friendly artificial intelligence applications.