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Structural batteries, which integrate mechanical load-bearing with electrochemical energy storage, offer a transformative solution for next-generation electric mobility. In this work, we present a novel and scalable dry- processing strategy for fabricating structural electrodes. Lithium nickel manganese cobalt oxide (NMC111) and graphite are used as the active materials for the positive and negative electrodes, respectively, with carbon fiber fabric serving as structural reinforcement and current collector. A conductive interfacial coating is applied to promote strong adhesion between the dry-processed electrodes and the carbon fiber fabric, ensuring both robust structural integrity and electrochemical performance. This approach enables ultrahigh mass loadings exceeding 30 mg cm− 2 —among the highest reported for structural battery electrodes. The resulting structural pouch cell delivers an energy density of 127 Wh kg− 1 and a Young's modulus of 3.2 GPa, yielding a multifunctional efficiency greater than 1.0. These results outperform conventional designs that separate structural and energy storage functions, offering significant mass savings at the system level. Overall, this work demonstrates the practical feasibility of integrating dry-processed electrodes into multifunctional battery architectures and provides a promising pathway toward lightweight, high-performance structural energy storage systems. 

We demonstrate the epitaxial growth of tetragonal platinum monoxide (PtO) on MgO, TiO2, and β-Ga2O3 single-crystalline substrates by ozone molecular-beam epitaxy. We provide synthesis routes and derive a growth diagram under which PtO films can be synthesized by physical vapor deposition. A combination of electrical transport and photoemission spectroscopy measurements, in conjunction with density functional theory calculations, reveal PtO to be a degenerately doped p-type semiconductor with a bandgap of Eg ≈ 1.6 eV. Spectroscopic ellipsometry measurements are used to extract the complex dielectric function spectra, indicating a transition from free-carrier absorption to higher photon energy transitions at E ≈ 1.6 eV. Using tetragonal PtO as an anode contact, we fabricate prototype Schottky diodes on n-type Sn-doped β-Ga2O3 substrates and extract Schottky barrier heights of ϕB > 2.2 eV. 

The high contact resistance of transition metal dichalcogenide (TMD) -based devices is receiving considerable attention due to its limitation on electronic performance. The mechanism of Fermi level (EF) pinning, which causes the high contact resistance, is not thoroughly understood to date. In this study, the metal (Ni and Ag)/Mo-TMDs surfaces and interfaces are characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning tunneling microscopy and spectroscopy, and density functional theory systematically. Ni and Ag form covalent and van der Waals (vdW) interfaces on Mo-TMDs, respectively. Imperfections are detected on Mo-TMDs, which leads to electronic and spatial variations. Gap states appear after the adsorption of single, and two metal atoms on Mo-TMDs. The combination of the interface reaction type (covalent or vdW), the imperfection variability of the TMD materials, and the gap states induced by contact metals with different weights are concluded to be the origins of EF pinning. 

Development of a high-performance, p-type oxide channel is crucial to realize all-oxide complementary metal–oxide semiconductor technology that is amenable to 3D integration. Among p-type oxides, α-SnO is one of the most promising owing to its relatively high hole mobility {as high as 21 cm2 V−1 s−1 has been reported [M. Minohara et al., J. Phys. Chem. C 124, 1755–1760 (2020)]}, back-end-of-line compatible processing temperature (≤400 °C), and good optical transparency for visible light. Unfortunately, doping control has only been demonstrated over a limited range of hole concentrations in such films. Here, we demonstrate systematic control of the hole concentration of α-SnO thin films via potassium doping. First-principles calculations identify potassium substitution on the tin site (KSn) of α-SnO to be a promising acceptor that is not (self)-compensated by native vacancies or potassium interstitials (Ki). We synthesize epitaxial K-doped α-SnO thin films with controlled doping concentration using suboxide molecular-beam epitaxy. The concentration of potassium is measured by secondary ion mass spectrometry, and its incorporation into the α-SnO structure is corroborated by x-ray diffraction. The effect of potassium doping on the optical response of α-SnO is measured by spectroscopic ellipsometry. Potassium doping provides systematic control of hole doping in α-SnO thin films over the 4.8 × 1017 to 1.5 × 1019 cm−3 range without significant degradation of hole mobility or the introduction of states that absorb visible light. Temperature-dependent Hall measurements reveal that the potassium is a shallow acceptor in α-SnO with an ionization energy in the 10–20 meV range. 

Tungsten transition metal dichalcogenides (W-TMDs) are intriguing due to their properties and potential for application in next-generation electronic devices. However, strong Fermi level (EF) pinning manifests at the metal/W-TMD interfaces, which could tremendously restrain the carrier injection into the channel. In this work, we illustrate the origins of EF pinning for Ni and Ag contacts on W-TMDs by considering interface chemistry, band alignment, impurities, and imperfections of W-TMDs, contact metal adsorption mechanism, and the resultant electronic structure. We conclude that the origins of EF pinning at a covalent contact metal/W-TMD interface, such as Ni/W-TMDs, can be attributed to defects, impurities, and interface reaction products. In contrast, for a van der Waals contact metal/TMD system such as Ag/W-TMDs, the primary factor responsible for EF pinning is the electronic modification of the TMDs resulting from the defects and impurities with the minor impact of metal-induced gap states. The potential strategies for carefully engineering the metal deposition approach are also discussed. This work unveils the origins of EF pinning at metal/TMD interfaces experimentally and theoretically and provides guidance on further enhancing and improving the device performance.