Nonvolatile Memristive Switching in Self-assembled Nanoparticle Dimers

The selective formation of heterogeneous nanoparticle (NP) agglomerates and their memristive switching properties are reported. Following surfactant-mediated self-assembly in suspension, agglomerates of silver nanocubes (AgNCs) and spherical silicon nanoparticles (SiNPs) are prepared in a bottom-up approach. Dimers comprising one AgNC and one SiNP are electrically contacted, and pronounced bipolar memristive switching is demonstrated. The formed nanoscale memristor junctions show in particular narrow distributions of the SET voltage, ON/OFF-resistance ratios in excess of three orders of magnitude, and good retention properties. Ex situ scanning electron microscopy studies directly support a switching model based on Ag-conductive filament formation in the polycrystalline SiNPs. We propose our self-assembled NP memristors as building blocks for the bottom-up construction of future 3D memristive networks.