Mechanically flexible BNNT–ZnO quantum dot nanocomposites for high-performance resistive memory applications

This work presents the development of an ultraflexible and non-volatile resistive switching memory device based on boron nitride nanotube (BNNT) rods uniformly decorated with zinc oxide quantum dots (ZnO QDs). The BNNT rod–ZnO QDs nanocomposites were synthesized through a controlled solution-based route, yielding a well-defined core–shell structure as formed by TEM and EDS analysis. The Al/BNNT rod–ZnO QDs/ITO/PET device exhibits distinct bistability and stable resistive switching behavior, enabled by the synergy between the charge trapping roles of insulating BNNT rod and ZnO QDs. The electrical properties of this memory device show an excellent ON/OFF current ratio of 1.8 × 10³, outstanding endurance of 6.4 × 10³ over approximately 2 × 10⁴ switching cycles, and stable retention with ON/OFF current ratio of 4.9 × 10³ even after measurements exceeding 10⁵ s. Moreover, the device maintains consistent electrical performance even under a bending radius of 3 cm, demonstrating excellent mechanical flexibility and operational stability. Analysis of the carrier transport behavior based on electrical characterization reveals a transition from ohmic conduction under high electric fields to trap-limited space-charge-limited conduction coupled with Fowler–Nordheim tunneling. These results demonstrate the promising potential of BNNT-based hybrid nanocomposites for next-generation flexible and transparent memory device applications.