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Vertically aligned nanocomposite (VAN) thin films have shown strong potential in oxide nanoionics but are yet to be explored in detail in solid-state battery systems. Their 3D architectures are attractive because they may allow enhancements in capacity, current, and power densities. In addition, owing to their large interfacial surface areas, the VAN could serve as models to study interfaces and solid-electrolyte interphase formation. Here, we have deposited highly crystalline and epitaxial vertically aligned nanocomposite films composed of a Li x La 0.32±0.05 (Nb 0.7±0.1 Ti 0.32±0.05 )O 3±δ -Ti 0.8±0.1 Nb 0.17±0.03 O 2±δ -anatase [herein referred to as LL(Nb, Ti)O-(Ti, Nb)O 2 ] electrolyte/anode system, the first anode VAN battery system reported. This system has an order of magnitude increased Li + ionic conductivity over that in bulk Li 3x La 1/3−x NbO 3 and is comparable with the best available Li 3x La 2/3−x TiO 3 pulsed laser deposition films. Furthermore, the ionic conducting/electrically insulating LL(Nb, Ti)O and electrically conducting (Ti, Nb)O 2 phases are a prerequisite for an interdigitated electrolyte/anode system. This work opens up the possibility of incorporating VAN films into an all solid-state battery, either as electrodes or electrolytes, by the pairing of suitable materials. 

Thermophotovoltaic (TPV) technology converts heat into electricity using thermal radiation. Increasing operating temperature is a highly effective approach to improving the efficiency of TPV systems. However, most reported TPV selective emitters degrade rapidly via. oxidation as operating temperatures increase. To address this issue, replacing nanostructured oxide‐metal films with oxide–oxide films is a promising way to greatly limit oxidation, even under high‐temperature conditions. This study introduces new all‐oxide photonic crystal designs for high‐temperature stable TPV systems, overcoming limitations of metal phases and offering promising material choices. The designs utilize both yttria‐stabilized zirconia (YSZ)/MgO and CeO₂/MgO combinations with a multilayer structure and stable high‐quality growth. Both designsexhibit positive optical dielectric constants with tunable reflectivity, measured via optical characterization. Thermal stability testing using in situ heating X‐ray diffraction (XRD) suggests high‐temperature stability (up to 1000 °C) of both YSZ/MgO and CeO₂/MgO systems. The results demonstrate a new and promising approach to improve the high‐temperature stability of TPV systems, which can be extended to a wide range of material selection and potential designs.

 

Ag nanostructures exhibit extraordinary optical properties, which are important for photonic device integration. Herein, we deposited Ag–LiNbO 3 (LNO) nanocomposite thin films with Ag nanoparticles (NPs) embedded into the LNO matrix by the co-deposition of Ag and LNO using a pulsed laser deposition (PLD) method. The density and size of Ag NPs were tailored by varying the Ag composition. Low-density and high-density Ag–LNO nanocomposite thin films were deposited and their optical properties, such as transmittance spectra, ellipsometry measurement, as well as angle-dependent and polarization-resolved reflectivity spectra, were explored. The Ag–LNO films show surface plasmon resonance (SPR) in the visible range, tunable optical constants and optical anisotropy, which are critical for photonic device applications.