Continuous fabrication of MOF-based memory elements via droplet microfluidic synthesis

Abstract

In today's information-driven society, the amount of generated and processed data is constantly increasing, requiring continuous advancements and refinements of memory components. With global digitalization, there is an urgent need for data storage devices meeting specific criteria: they should be energy-efficient and compact, possess high capacity, and rapid information read/write rates, while being sustainable and made of recyclable materials. In this context, metal–organic frameworks (MOFs) could become efficient alternative materials for memory device creation due to their simple synthesis, scalability, and low energy consumption. The fabrication process for MOF-based memory elements is straightforward and efficient. Here we propose MOFs (HKUST-1) synthesis using an innovative approach based on droplet microfluidics that allows MOFs synthesis in 32 s, which can be used for further fabrication of memory elements. After revealing optimized experimental synthesis conditions by numerical simulation of droplet formation in a channel of a microfluidic chip, we obtain HKUST-1 microcrystals of various crystallinities and sizes by adjusting the reaction temperature and flow rates. We conduct a thorough structural and optical investigation of the resulting HKUST-1 microcrystals, which we further deposit on a conductive platform to form a memristive element. The memory device made from MOF microcrystals developed using droplet microfluidics demonstrates a higher ON/OFF ratio and faster fabrication compared to conventionally synthesized MOFs.