Inkjet printing cellulose nanofibril/PVA hybrid dielectrics for large hysteresis and high-performance a-IGZO synaptic transistors

Inkjet printing green nanomaterials for high-performance synaptic transistors is a hot research topic in academic communities. However, it remains challenging to develop printable and sustainable dielectric inks for the devices with desirable properties of nonvolatile behavior and large hysteresis, which are the basis for emulating controllable weight update in neuron computing. To address this challenge, we present a solution by fabricating a biodegradable cellulose nanofibril (CNF) dielectric film through inkjet printing, which serves as the source of hysteresis in amorphous indium–gallium–zinc oxide (a-IGZO) synaptic transistors. By employing suitable additives and meticulously engineered microfluidic flows, we have successfully achieved the high-quality CNF/polyvinyl alcohol (PVA) composite electrolyte films by inkjet-printing. This accomplishment has enabled the emulation of excellent synaptic functionalities, including short-term to long-term potentiation/depression, as well as the implementation of a nearly symmetric and linear weight update protocol. This work holds significant promise in advancing the development of cost-effective and environmentally friendly synaptic electronics.