Inkjet Printed Metal–Organic Frameworks for Non‐Volatile Memory Devices Suitable for Printed RRAM

Inkjet printing has emerged as a promising technique for patterning functional materials, offering significant advantages over traditional subtractive thin‐film methods. Its versatility enables the structuring of various materials, expanding application ranges and minimizing waste through additive manufacturing. However, the limited availability of functional material‐based inks suitable for inkjet printing presents challenges in ink formulation. HKUST‐1, a 3D cubic metal–organic frameworks (MOFs) comprised of copper(II) ions coordinated to benzene‐1,3,5‐tricarboxylate (BTC) organic linkers, known for its porosity and tunability, have potential to enhance inkjet‐printed devices. This study combines inkjet printing and evaporation‐induced crystallization to structure HKUST‐1, marking the first demonstration of nanocrystalline HKUST‐1 integrated into a printed electronic device, specifically a memristor, where the MOF is prepared by inkjet printing of a precursor solution. Memristors, which change their resistance based on the external stimuli history, enabling the construction of resistive random‐access memory (RRAM). The fabricated memristors in this study exhibit notable properties: low forming voltage, an Roff/Ron ratio of 104, a retention time of 600 s, and endurance exceeding 60 write and erase cycles. This research highlights the potential of integrating MOFs into inkjet printing, unlocking broader application possibilities, and advancing additive manufacturing for functional materials. Inkjet printing enables efficient patterning of functional materials. This study pioneers nanocrystalline HKUST‐1, a metal‐organic framework (MOF), in a printed memristor via inkjet printing of a precursor solution. The nonvolatile memristor exhibits notable performance (Roff/Ron: 104, forming free), showcasing MOFs′ potential to expand applications and advance functional material manufacturing.