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DOE OSTI · 1897729

On-Surface Single-Molecule Identification of Mass-Selected Cyclodextrin-Supported Polyoxovanadates for Multistate Resistive-Switching Memory Applications

Yang, Fangshun·Moors, Marco·Hoang, Duc Anh·Schmitz, Sebastian·Rohdenburg, Markus·Knorke, Harald·Charvat, Ales·Wang, Xue-Bin·Monakhov, Kirill Yu.·Warneke, Jonas
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Abstract

Polyoxovanadate anions immobilized on conducting substrates are promising candidates for molecule-based memory technologies. However, strong electronic interactions with the substrate and the formation of larger agglomerates remain bottlenecks on the way to their technical application. We demonstrate that ion soft-landing of mass selected cyclodextrin- functionalized hexavanadates enables to deposit these host-guest complexes as single memory units on surfaces without their quaternary ammonium countercations from solution. The cyclodextrin provides a stabilizing “shell” for the dianions. Further, multistate switching evidenced by the change in molecular resistance has been detected using scanning tunneling microscopy and spectroscopy and attributed to reduction of individual vanadium (+V) centers.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYmacrocyclic moleculesmolecular electronicsmolecular multi-level switchingpolyoxovanadatescanning probe microscopysoft-landingsupramolecular self-assembly

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Yang, Fangshun, Moors, Marco, Hoang, Duc Anh, Schmitz, Sebastian, Rohdenburg, Markus, Knorke, Harald, Charvat, Ales, Wang, Xue-Bin, Monakhov, Kirill Yu., Warneke, Jonas. 2022-09-22. On-Surface Single-Molecule Identification of Mass-Selected Cyclodextrin-Supported Polyoxovanadates for Multistate Resistive-Switching Memory Applications. https://doi.org/10.1021/acsanm.2c03025

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