Bridging the scales: Advanced scanning probe microscopy across molecular redox regimes
*Correspondence to:
Noah Al-Shamery, Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany.
E-mail: noahcoelestin.alshamery@leibniz-iom.de
Kirill Monakhov, Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany. E-mail: kirill.monakhov@iom-leipzig.de
Kirill Monakhov, Leibniz Institute of Surface Engineering (IOM), 04318 Leipzig, Germany. E-mail: kirill.monakhov@iom-leipzig.de
Smart Mater Devices. 2027;3:202646. 10.70401/smd.2026.0054
Received: July 30, 2026Accepted: October 09, 2026Published: October 12, 2026
This article belongs to the Special lssue Intelligent Soft and Organic Matter: Fundamentals, Electrochemistry, and Sensing
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Abstract
Redox-active ligands, metal complexes, and larger coordination frameworks are chemically precise, responsive building blocks for smart materials, molecular electronics, energy storage, and neuromorphic device concepts. However, their redox behavior depends strongly on the experimental regime in which it is probed. Bulk electrochemistry, confined nanodroplet methods, electrochemical scanning probe microscopy, tunneling spectroscopy, and synchrotron-coupled nanospectroscopy often probe the same molecular event through fundamentally different physical observables. In this mini-review, we use polyoxometalates as a guiding molecular class to compare redox behavior across three length-scale regimes: bulk ensembles, confined nanoscale assemblies, and single-molecule or few-molecule junctions. We discuss cyclic voltammetry, scanning electrochemical probe methods, electrochemical scanning tunneling microscopy, scanning tunneling spectroscopy, electron-spin-resonance STM, scattering-type near-field optical microscopy, and synchrotron nanospectroscopic methods. We argue that advanced scanning probe microscopy provides the missing conceptual and experimental bridge between classical electrochemical redox potentials and nanoscale electronic charge and spin structure, enabling a regime-aware design language for redox-programmable molecular materials.
Keywords
Scanning probe microscopy, electrochemistry, polyoxoanions, SECCM, EC-STM, s-SNOM, smart materials, solution-processable electronics
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Al-Shamery N, Vicente RA, Zocher C, Kersting B, Monakhov K. Bridging the scales: Advanced scanning probe microscopy across molecular redox regimes. Smart Mater Devices. 2027;3:202646. https://doi.org/10.70401/smd.2026.0054
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Al-Shamery N, Vicente RA, Zocher C, Kersting B, Monakhov K. Bridging the scales: Advanced scanning probe microscopy across molecular redox regimes. Smart Mater Devices. 2027;3:202646. https://doi.org/10.70401/smd.2026.0054
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