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Metal‐semiconductor interfaces are crucial components of optoelectronic and electrical devices, the performance of which hinges on intricate dynamics involving charge transport and mechanical interaction at the interface. Nevertheless, structural changes upon photoexcitation and subsequent carrier transportation at the interface, which crucially impact hot carrier stability and lifetime, remain elusive. To address this long‐standing problem, they investigated the electron dynamics and resulting structural changes at the Au/TiO2 interface using ultrafast electron diffraction (UED). The analysis of the UED data reveals that interlayer electron transfer from metal to semiconductor generates a strong coupling between the two layers, offering a new way for ultrafast heat transfer through the interface and leading to a coherent structural vibration that plays a critical role in propagating mechanical stress. These findings provide insights into the relationship between electron transfer and interfacial mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

[Display omitted] Nickel-based catalysts are suitable for water splitting to generate hydrogen. However, the low conductivity and weak stability have always been urgent issues to be addressed in nickel-based catalysts. Fe-doped nickel oxide/nickel phosphide (Fe-NiO/Ni 2 P) was prepared as a bifunctional electrocatalyst by doping metal and constructing heterogeneous interface. The introduction of Fe contributed to the reinforced interfacial coupling effect of NiO/Ni 2 P to promote charge transfer and accelerate reaction kinetics. The heterojunction regulated the interfacial charge density between NiO and Ni 2 P to improve the electronic environment of Ni2+ and enhance conductivity. The O-Fe-P bond at the heterogeneous interface induced the directional transfer of electrons and ensured the structure stability. The synergistic effect of Fe doping and heterogeneous interface increased the adsorption energy of *O and coordinated the adsorption energy of *H, advancing the catalytic performance. Fe-NiO/Ni 2 P exhibited the overpotential of 242 mV and 141 mV at 10 mA cm−2 for oxygen and hydrogen evolution, respectively. [ABSTRACT FROM AUTHOR]

Elaborate engineering of heterostructure and composition to regulate the electroactivities remains a pronounced challenge. Herein, a self-supported 2D/2D heterostructure monolith is constructed by interlinked FeCo-hydroxides nanosheets tightly interlacing with aligned Cu 0.76 Co 2.24 O 4 nanoplates. Due to the well-defined hierarchical nanoarrays and desirable interfacial coupling, the monolithic catalyst can guarantee the rapid charge transfer and mass transport pathways for accelerated surface kinetics, leading to manifestly improved electroactivities and stability toward trifunctional catalysis. Both experimental and theoretical calculations unravel the enriched multimetal active sites for intermediates adsorption and the synergistic interplay of the heterostructure to achieve enhanced catalytic efficiency. Consequently, the heterostructure catalyst contributes to high-performance rechargeable/flexible all-solid-stated Zn-air batteries and water electrolyzer with an ultralow potential of 1.51 V. Moreover, self-powered water splitting system driven by flexible Zn-air batteries delivers a high H 2 generation rate. This cost-effective heterostructure monolith could open an intriguing avenue for advancing all-in-one films toward portable energy conversion/storage. [Display omitted] • A self-supported 2D/2D heterostructure monolith with rich multi-metal active sites is constructed from CuCo-oxides. • The monolithic catalyst exhibits superior multifunctional activities for HER/OER/ORR. • Rechargeable ZABs obtain high specific energy and excellent cycling stability for 400 h. • The overall water splitting cell delivers an ultralow potential of 1.51 V to achieve 10 mA cm−2. • Self-powered water splitting system driven by flexible ZABs is developed for H 2 production. [ABSTRACT FROM AUTHOR]

The interfacial coupling in epitaxially grown bilayers composed of paramagnetic CaIrO 3 and ferromagnetic LaMnO 3 bilayers has been shown to give rise to an unexpected exchange bias effect. Systematic magnetic measurements ascribe this effect to the existence of an interfacial spin-cluster-like state in the bilayers. Furthermore, by tuning the epitaxial strains in the bilayers with different growth sequences, a much stronger exchange bias effect is observed in the CaIrO 3 /LaMnO 3 bilayer rather than the LaMnO 3 /CaIrO 3 bilayer, revealing the indispensable role of epitaxial strains in engineering the interfacial coupling. [ABSTRACT FROM AUTHOR]

The atomically interfacial engineering combined with the rational architecture design is of significant important for developing promising oxygen electrocatalysts towards efficient energy-related applications, but still remains a grand challenge. Herein, we report numerous CoFe alloy nanoparticles, with tunable compositions, anchored firmly over the well-designed oxygen-dopants-rich carbon nanoboxes (CoFe@C NBs) as an active electrocatalyst for electrochemical oxygen reduction reaction (ORR), which is fabricated via a facile cation exchange and pyrolysis strategy. Thanks to the robust interfacial electronic coupling and the highly-exposed synergetic bimetallic centers, this optimized CoFe-27 @C NBs with the Co: Fe atomic ratio of 5.4: 1 could exhibit superior activity, excellent long-term stability and high methanol tolerance during a long-term ORR operation, with an excellent half-wave potential of 0.90 V and decent limiting current density of 5.4 mA cm−2, comparable with the commercial Pt/C catalysts and being one of the most active transition-metal ORR electrocatalysts developed. By the atomic-level synchrotron radiation characterizations and the detailed electrochemical measurements, it can be found that the strong electronic coupling at the metal-support interface could effectively promote the charge transfer and catalytic reaction kinetics, contributing to efficient 4e- ORR for CoFe-27 @C NBs. [Display omitted] • A novel cation exchange and multiple-step pyrolysis strategy is developed. • Synergetic CoFe alloy embedded on oxygen-dopant-rich carbon nanobox is fabricated. • Strong alloy-support coupling via robust interfacial chemical bonds is revealed. • The unique CoFe@C nanoboxes are highly-active for oxygen electrocatalysis. [ABSTRACT FROM AUTHOR]

• BiOBr-PVP composites were firstly fabricated by the facile precipitation method. • BiOBr-PVP exhibited excellent photocatalytic RhB and TC oxidation, and Cr(VI) reduction. • The surface and band structure of BiOBr can be modified by PVP with more active sites and radicals available. • The charge transfer pathway and internal mechanism between BiOBr and PVP were proposed. Designing semiconductor catalysts with superior charge carrier transfer and adequately exposed reactive sites is crucial for acquiring remarkable photocatalytic activity. Herein, a series of BiOBr catalysts with PVP as "organic armor" were synthesized via a facile precipitation strategy. As expected, the BiOBr-PVP hybrids exhibited superior catalytic oxidation toward the removal of organic dyes and tetracycline, but also catalytic reduction of Cr (VI). By virtue of tunable bandgap structure, sufficient abundance of reactive sites and decreased work function, the BiOBr-PVP composites could effectively expedite the charge carrier separation and transfer via enhanced transport pathways. Simultaneously, the reduced particle size and enlarged specific surface area achieved by loading PVP on the BiOBr catalyst could provide greater contact area and channels for intimate interaction between reactive sites and pollutants. Moreover, a photodegradation pathway for tetracycline was proposed based on LC-MS measurement and the intrinsic mechanism between BiOBr and PVP was discussed by first-principles calculation. The constructed BiOBr-PVP composites extend the scope and comprehension of photocatalysts via surface structural engineering and sufficient interfacial coupling for use in several environmental purification applications. [ABSTRACT FROM AUTHOR]

Here, crystal structure, electronic structure, chemical substitution, pressure-dependent superconductivity, and thickness-dependent properties in FeSe-based superconductors are systemically reviewed. First, the superconductivity versus chemical substitution is reviewed, where the doping at Fe or Se sites induces different effects on the superconducting critical temperature (Tc). Meanwhile, the application of high pressure is extremely effective in enhancing Tc and simultaneously induces magnetism. Second, the intercalated-FeSe superconductors exhibit higher Tc from 30 to 46 K. Such an enhancement is mainly caused by the charge transfer from the intercalated organic and inorganic layer. Finally, the highest Tc emerging in single-unit-cell FeSe on the SrTiO3 substrate is discussed, where electron-phonon coupling between FeSe and the substrate could enhance Tc to as high as 65 K or 100 K. The step-wise increment of Tc indicates that the synergic effect of carrier doping and electron-phonon coupling plays a critical role in tuning the electronic structure and superconductivity in FeSe-based superconductors. [ABSTRACT FROM AUTHOR]