Polyvinylammonium-immobilized FAPbI3 Perovskite Grains for Flexible Fibrous Woven RRAM Array

Abstract Woven resistive random access memory (RRAM) is a promising subject in flexible wearable electronic devices. In this work, polyvinylammonium iodate (PVAm·HI) is added to the FAPbI 3 perovskite precursor solution to fabricate a flexible fibrous woven RRAM array by improving the flexibility and stability of FAPbI 3 perovskite. The long carbochain polymer backbone of PVAm serves as nucleation sites and a growth template to improve the perovskite crystallization process, and to in situ crosslink the perovskite grains at the crystal interface. The functional Al@FAPbI 3 :PVAm fibers are then prepared by solution dip-coating to assemble the fibrous crosspoint RRAM device with the structure of Al@FAPbI 3 :PVAm/Al by crossing bare aluminum (Al) fibers with functional fibers. Compared to a pristine device, the PVAm-modified devices exhibit a considerable improvement in the ON/OFF ratio and environmental stability. Specifically, the 2% PVAm-modified FAPbI 3 RRAM devices show an evident bipolar resistive switching (RS) behavior with a high ON/OFF ratio of 10 9 , which can easily achieve multilevel storage by setting the compliance current ( I cc ) to increase the storage density in the crosspoint array. Interestingly, a 100-times bent plastics-encapsulated device still exhibits a good RS behavior. This work provides a facile approach to achieve high-density storage in flexible wearable electronic devices. Graphical Abstract