Taking advantage of electrode thicknesses well beyond conventional dimensions allowed us to follow the surface plasmonic THz frequency phenomenon with vacuum wavelengths of 100 μm to 1 mm, only to scrutinize them within millimeters-thicknesses insulators. Here, we analyze an Al/insulator/Cu cell in which the metal electrodes-collectors were separated by a gap that was alternatively filled by SiO2, MgO, Li2O, Na3Zr2Si2PO12–NASICON, Li1.5Al0.5Ge1.5(PO4)3–LAGP, and Li2.99Ba0.005ClO–Li+ glass. A comparison was drawn using experimental surface chemical potentials, cyclic voltammetry (I-V plots), impedance spectroscopy, and theoretical approaches such as structure optimization, simulation of the electronic band structures, and work functions. The analysis reveals an unexpected common emergency from the cell’s materials to align their surface chemical potential, even in operando when set to discharge under an external resistor of 1842 Ω.cminsulator. A very high capability of the metal electrodes to vary their surface chemical potentials and specific behavior among dielectric oxides and solid electrolytes was identified. Whereas LAGP and Li2O behaved as p-type semiconductors below 40 °C at OCV and while set to discharge with a resistor in agreement with the Li+ diffusion direction, NASICON behaved as a quasi n-type semiconductor at OCV, as MgO, and as a quasi p-type semiconductor while set to discharge. The capacity to behave as a p-type semiconductor may be related to the ionic conductivity of the mobile ion. The ferroelectric behavior of Li2.99Ba0.005ClO has shown surface plasmon polariton (SPP) waves in the form of surface propagating solitons, as in complex phenomena, as well as electrodes’ surface chemical potentials inversion capabilities (i.e., χ (Al) − χ (Cu) > 0 to χ (Al) − χ (Cu) < 0 vs. Evacuum = 0 eV) and self-charge (ΔVcell ≥ +0.04 V under a 1842 Ω.cminsulator resistor). The multivalent 5.5 mm thick layer cell filled with Li2.99Ba0.005ClO was the only one to display a potential bulk difference of 1.1 V. The lessons learned in this work may pave the way to understanding and designing more efficient energy harvesting and storage devices.

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The advent of new solid-state energy storage devices to tackle the electrical revolution requires the usage of nonlinear behavior leading to emergent phenomena. The ferroelectric analyzed herein belongs to a family of electrolytes that allow energy harvesting and storage as part of its self-charging features when thermally activated. The Na 2.99 Ba 0.005 ClO electrolyte shows quasi-adiabatic behavior with a continuous increase in polarization upon cycling, displaying almost no hysteresis. The maximum polarization obtained at a weak electric field is giant and similar to the remanent polarization. It depends on the temperature with a pyroelectric coefficient of 5.37 C m −2 °C−1 from −5 to 46 °C. The emergence occurs via negative resistance and capacitance. The glass transition is found to have its origins in the sharp depolarization at 46 -48 °C. Above -10 °C, at ≈ -5 °C, another thermal anomaly may rely on the topologic characteristics of the A 3-2x Ba x ClO (A = Li, Na, K) glass electrolytes enabling positive feedback of the current of electrons throughout the surface of the inner cell. The phenomena may pave the way toward a better understanding of dipolar nanodomain fragile glasses with exceptional ferroelectric characteristics to architect energy harvesting and storage devices based on multivalent thermally activated Na + -ion-ion electrolytes.

Interfacial additives such as oxides may help solve diffusion and nucleation obstacles in heterojunctions of solid-state devices. Healing strategies may rely on them, particularly in ZnO, which has numerous applications, from photovoltaics and sensors to superconductors and batteries as a lithiumphilic interlayer. Here, we show a case study based on in operando cells with two heterojunctions and the ZnO as a dielectric semiconductor. The cells show how the Cu/ZnO surface chemical potentials equalize by forming a more negatively charged region where nucleation of a new phase will likely be facilitated and the dielectric's role in interlaying with negative and positive electrodes. The highly ohmic behavior of the interface, negative electrode (metal)/dielectric, is also analyzed. The advantage of the scanning Kelvin probe (SKP) in studying the surface chemical potentials is demonstrated. Ab initio simulations used density functional theory (DFT) and hybrid functional HS06 to determine the bulk ZnO's band structure and optical properties, including relative permittivities. Aluminum, zinc, copper, and zinc oxide work functions were obtained after simulating the correspondent surfaces and compared with contact potentials obtained with SKP. The study extends hyperbolically into the cell's dimensions to understand all of the interplays of the components. An unexpected long-range equalization of the surface chemical potentials of the three cell constituents away from the interfaces may mirror a metal−insulator−metal plasmonic interaction that can be tailored for solar applications.

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