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The dynamics of ferroelectric domain switching are directly mapped in a PbZr_0.2Ti_0.8O₃thin film using piezoresponse force microscopy. Employing the rastering tip as a poling electrode to locally apply a fixed bias near the coercive field, while simultaneously monitoring the evolving domain pattern during continuous imaging, the effectively independent switching dynamics for numerous domains are directly investigated. While areal poling follows the anticipated S‐curve, this is shown to be the collective outcome of linear terminal radial growth for an ensemble of independently nucleating domains. By repeating such spatially resolved measurements in the same region, but with progressively greater fields, nucleation sites and growth patterns are shown to clearly repeat. This reveals apparent defects which comparatively promote switching, and nucleation times and growth rates that accelerate exponentially. After analyzing and mapping the ratio of activation energies for nucleation to growth, a high density of nucleation sites can possibly be activated with higher poling fields—even if only at the start of a poling process—enabling faster and more efficient switching to be engineered as directly demonstrated.

To satisfy continual demands for higher performance dielectrics in multi‐layer ceramic capacitors and related microelectronic devices, novel characterization methods are necessary for mapping materials properties down to the nanoscale, where enabling materials developments are increasingly relevant. Accordingly, an atomic force microscopy‐based approach is implemented for characterizing insulator performance based on the mapping of discharging dynamics. Following surface charging by biasing a conducting tip contacting a dielectric surface, consecutive non‐contact Kelvin force surface potential mapping (KPFM) reveals charge dissipation via exponential decay. In barium titanate (BTO) thin films engineered with distinct microstructures but identical thicknesses, discharging rates vary by up to a factor of 2, with smaller grain size correlating to longer dissipation times, providing insight into optimal microstructures for improved capacitor performance. High‐resolution potential mapping as a function of time thereby provides a route for directly investigating charge injection and discharging mechanisms in dielectrics, which are increasingly engineered down to the nanoscale and have global implications given the trillions of such devices manufactured each year.

Ferroelectric domain walls are quasi‐2D systems that show great promise for the development of nonvolatile memory, memristor technology, and electronic components with ultrasmall feature size. Electric fields, for example, can change the domain wall orientation relative to the spontaneous polarization and switch between resistive and conductive states, controlling the electrical current. Being embedded in a 3D material, however, the domain walls are not perfectly flat and can form networks, which leads to complex physical structures. In this work, the importance of the nanoscale structure for the emergent transport properties is demonstrated, studying electronic conduction in the 3D network of neutral and charged domain walls in ErMnO₃. By combining tomographic microscopy techniques and finite element modeling, the contribution of domain walls within the bulk is clarified and the significance of curvature effects for the local conduction is shown down to the nanoscale. The findings provide insights into the propagation of electrical currents in domain wall networks, reveal additional degrees of freedom for their control, and provide quantitative guidelines for the design of domain‐wall‐based technology.

The organic insulator–metal interface is the most important junction in flexible electronics. The strong band offset of organic insulators over the Fermi level of electrodes should theoretically impart a sufficient impediment for charge injection known as the Schottky barrier. However, defect formation through Anderson localization due to topological disorder in polymers leads to reduced barriers and hence cumbersome devices. A facile nanocoating comprising hundreds of highly oriented organic/inorganic alternating nanolayers is self‐coassembled on the surface of polymer films to revive the Schottky barrier. Carrier injection over the enhanced barrier is further shunted by anisotropic 2D conduction. This new interface engineering strategy allows a significant elevation of the operating field for organic insulators by 45% and a 7× improvement in discharge efficiency for Kapton at 150 °C. This superior 2D nanocoating thus provides a defect‐tolerant approach for effective reviving of the Schottky barrier, one century after its discovery, broadly applicable for flexible electronics.