Eco-Friendly Polyfluorene/Poly(butylene succinate) Blends and Their Electronic Device Application on Biodegradable Substrates

We report an environmentally friendly resistive switching memory device on a biodegradable Ecoflex elastomeric substrate using nontoxic and disintegrable polyfluorene/poly(butylene succinate) (PFN/PBS) blend thin films. Via applying different processing techniques, involving spin coating, spray coating, and solution shearing, the scale of phase-separated morphology could be tuned from 115.4 ± 30 nm using spin coating to 10.1 ± 3 nm using solution shearing. The dramatic reduction in PFN domain size gave rise to the enhancement of photoluminescence efficiency (16.0% for the solution-sheared film) and diverse changes in resistive switching behaviors, including dynamic random access memory- and write-once-read-many times (WORM)-type characteristics. The eco-friendly resistive switching memory device with the AgNW/(PFN/PBS solution-sheared film)/AgNW/Ecoflex sandwich structure exhibited nonvolatile WORM-type characteristics, comprising a high on/off current ratio of 1010, low threshold voltage of 2.6 V, and outstanding stability for 7000 s. Besides, the memory characteristics could maintain a high on/off current ratio of 109 after a 100 times cyclic bending test. The result indicates promising potential to reduce environmental footprints for wearable electronics.