Stable Bipolar Resistive Switching in Lead-Free Cs₂AgBiBr₆ Memristors for Neuromorphic Computing

Area of Science:

• Materials Science
• Solid-State Physics
• Device Engineering

Background:

• Lead-halide perovskites are widely used in photoelectric devices but raise toxicity concerns.
• Lead-free double-perovskite Cs2AgBiBr6 offers a stable, non-toxic alternative.
• Advancements are needed for ecofriendly photoelectric and memory devices.

Purpose of the Study:

• To synthesize lead-free Cs2AgBiBr6 films using a simplified method.
• To fabricate and characterize Cs2AgBiBr6-based memristors.
• To evaluate the potential of Cs2AgBiBr6 for neuromorphic computing and data storage.

Main Methods:

• Spin-coating of Cs2AgBiBr6 films on FTO glass in a dry-air glovebox.
• Fabrication of memristors using Cs2AgBiBr6 films.
• Characterization of resistive switching behavior, endurance, retention, and stability.
• Machine learning simulations to assess synaptic function mimicry.

Main Results:

• Uniform Cs2AgBiBr6 films with low roughness were synthesized.
• Memristors exhibited stable bipolar resistive switching with low operating voltages (+0.4 V, -0.3 V).
• Achieved an on/off ratio of 479, 1000 cycles endurance, and 10^4 s retention.
• Demonstrated stable resistance ratio (~441) after 30 days ambient storage.
• Attained 91.39% accuracy in machine learning simulations mimicking synaptic functions.

Conclusions:

• Cs2AgBiBr6 is a viable material for stable and efficient memristors.
• The developed synthesis method is simple and avoids antisolvent or inert gas.
• Cs2AgBiBr6-based memristors show potential for sustainable neuromorphic computing and information storage.