Nanoscale resistive switching in electrodeposited MOF Prussian blue analogs driven by K-ion intercalation probed by C-AFM

TL;DR

This study demonstrates nanoscale resistive switching in PBA-based memristors driven by K-ion intercalation, visualized with C-AFM, highlighting their potential for high-speed, scalable neuromorphic and memory devices.

Contribution

It introduces PBA-based intercalation memristors with scalable nanoscale switching, fast operation, and compatibility with CMOS fabrication, a novel application of PBAs in memristive technology.

Findings

Reversible conductance modulation via K-ion intercalation visualized at sub-100 nm scale.

Operates at high speeds up to 200 V/s, suitable for fast neuromorphic applications.

Fabrication is low-cost, aqueous, room-temperature, compatible with large-scale processing.

Abstract

K-ion intercalation in Prussian blue analogs (PBAs) is a well-established charge storage mechanism in potassium-ion batteries; here, we demonstrate that this same ion intercalation process is the basis for nanoscale resistive switching behavior in PBA-base memristive devices. Using C-AFM, we directly visualize and electrically control this intercalation process within sub-100 nm volumes, revealing reversible, localized conductance modulation driven by K-ion intercalation and Fe^(2+)/Fe^(3+) redox reconfiguration. This nanoscale operability highlights the exceptional potential of PBAs for high-scalable and low-dimension memristor-based devices integration. Due to their modular composition, PBAs constitute a chemically rich, earth-abundant materials platform whose electronic and ionic properties can be precisely tuned for specific device functions. K-ion intercalation PBA-based memristor devices, with their single-step, aqueous, and room-temperature fabrication, enable low-cost, large-scale processing compatible with CMOS, without any additional post-fabrication processing. Our findings establish PBAs as a new class of intercalation memristors with scalable nanoscale switching and exceptional materials versatility, toward highly integrated neuromorphic and non-volatile memory technologies. This work provides the first demonstration of intercalation-driven resistive switching under ultrafast voltage sweeps, with PW operating up to 200 V/s and PB up to 50 V/s. This unprecedented speed establishes PBAs as a distinct, high-rate class of K-ion intercalation memristors suitable for fast, high-density neuromorphic and memory applications.