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Interfaces of metal oxide heterojunctions display a variety of intriguing physical properties that enable novel applications in spintronics, quantum information, neuromorphic computing, and high‐temperature superconductivity. One such LaAlO3/SrTiO3 (LAO/STO) heterojunction hosts a 2D electron liquid (2DEL) presenting remarkable 2D superconductivity and magnetism. However, these remarkable properties emerge only at very low temperatures, while the heterostructure fabrication is challenging even at the laboratory scale, thus impeding practical applications. Here, a novel plasma‐enabled fabrication concept is presented to develop the TiO2/Ti3O4 hetero‐phase bilayer with a 2DEL that exhibits features of a weakly localized Fermi liquid even at room temperature. The hetero‐phase bilayer is fabricated by applying a rapid plasma‐induced phase transition that transforms a specific portion of anatase TiO2 thin film into vacancy‐prone Ti3O4 in seconds. The underlying mechanism relies on the screening effect of the achieved high‐density electron liquid that suppresses the electron‐phonon interactions. The achieved "adiabatic" electron transport in the hetero‐phase bilayer offers strong potential for low‐loss electric or plasmonic circuits and hot electron harvesting and utilization. These findings open new horizons for fabricating diverse multifunctional metal oxide heterostructures as an innovative platform for emerging clean energy, integrated photonics, spintronics, and quantum information technologies. [ABSTRACT FROM AUTHOR]

All-solid-state lithium batteries have become a popular research topic due to their excellent potential in the realization of improved energy density and safety. Solid-state electrolytes are the key components of all-solid-state lithium batteries. Among them, oxide solid electrolytes (OSEs) have the advantages of wide electrochemical window, acceptable ionic conductivity, good thermal stability, and high mechanical strength. However, there are still some issues with thick OSE pellets and inadequate interface contact. In this review, we summarize the research progress in OSEs and introduce the preparation methods of thin OSE films, such as slurry casting, tape casting and solvent-free methods. Besides, the general strategies for improving interface contact and reducing interfacial impedance between OSEs and the cathode/anode are expounded, respectively. Finally, an outlook for the future development of OSEs toward industrial production and practical applications is provided. [ABSTRACT FROM AUTHOR]

α‐phase formamidine lead iodine (α‐FAPbI3) as a competitive candidate to pursue high‐performance perovskite solar cells (PSCs) suffers from the weakness of random nucleation and disordered growth in chasing high‐grade polycrystalline films. Here, single‐crystal seeds crystallization (SCSC) method is proposed to obtain high‐quality α‐FAPbI3 perovskite films for the first time. Six single‐crystals seeds (CsPbBr3, CsPbI3, FAPbBr3, FAPbI3, MAPbBr3, and MAPbI3) are employed to regulate α‐FAPbI3 perovskite crystallization. These seeds act as nucleation sites and allow the perovskite to grow directly. The rapid crystallization significantly improves the crystallinity of perovskite films with uniform morphology, large grain size, and less defects. Of particular note, FAPbBr3 seed prefers to grow α‐FAPbI3 epitaxially from FAPbBr3@PbI2 heterostructure through a halogen anion exchange process. The average grain size of FAPbBr3‐perovskite film is boosted to 2.6 µm, and the trap density reduced by 11 times. The resultant FAPbBr3‐PSCs achieve a maximum power conversion efficiency (PCE) of 23.84% with a high open‐circuit voltage of 1.18 V. The unencapsulated PSC retains 91% of the initial PCE after 3000 h of storage at ≈30–50% relative humidity and preserves 98.5% of the original value after 155 h illumination with maximum power point tracking. [ABSTRACT FROM AUTHOR]