2, Pohang University of Science and Technology (POSTECH), Pohang, , Korea (the Republic of)
3, Research Institute of Advanced Materials, Seoul National University, Seoul, , Korea (the Republic of)
4, BK21 PLUS SNU Materials Division for Educating Creative Global Leaders, Seoul National University, Seoul, , Korea (the Republic of)
Organic/inorganic hybrid perovskite (OHP) has been recently highlighted as a next-generation material of electronic devices such as light emitting diodes, and solar cells and memory devices . In particular, significant hysteresis caused by huge ion migration of OHP is a very valuable property for memory devices such as neuromorphic synaptic memory . In recent study, by using methylammonium lead bromide perovskite (MAPbBr3), two-terminal artificial synapse was demonstrated, and it showed typical synaptic properties caused by ion migration in the perovskite layer . However, previously reported perovskite artificial synapse still needs to be improved in terms of memory retention time and cyclic operation stability. To overcome above issues, here, we report artificial synaptic devices based on polymer-blended perovskite layer. Substitutional polymers in the perovskite structure have an important role for improving ion migration as well as ion trapping in the trap sites such as grain boundaries, interface of layers and so on. In this way, ions can be easily moved when voltage was applied, and then, they cannot return to the original position when the voltage was removed; this mechanism induced long current retention time of perovskite-based artificial synapse memory . Furthermore, passivating effect caused by substitutional polymers can suppress degradation of electrical property of perovskite layer. We expect that our approach would expand the research field of neuromorphic electronics using perovskite materials.
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