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Intermetallic nanocrystals are emerging materials for energy, catalysis, and biomedical applications, but combining two or more metals at the nanoscale remains challenging. The amalgamation reaction represents a convenient method for hundreds of intermetallic compositions, as it relies on fast and efficient alloying of liquid metals into presynthesized metallic seeds. Here, Pd–Zn nanocrystals, prepared via Zn amide thermolysis on the surface of Pd nanocrystals and subsequent amalgamation alloying, are investigated. Size‐uniform nanocrystals and control over a wide range of Pd–Zn compositions are achieved. This allows deriving a phase diagram at the nanoscale, in which miscibility gaps and three phases with broad solid solutions are detected. Furthermore, the formation of homogeneous ZnO shells for Pd–Zn compositions extending beyond phase solubility limits is observed. Full chemistry control for Pd–Zn nanocrystals enables a rational choice of materials for selected energy applications, achieveing an extended lifetime of Zn‐ion batteries for Zn‐rich PdZn2 stoichiometry, superior electrocatalytic properties for nearly stoichiometric PdZn halite phase, and the stability and efficiency of high‐voltage cathodes benefiting from ZnO shell protection around Pd3Zn10 nanocrystals are reported. This paper exemplifies the multifunctionality of intermetallics Pd–Zn nanocrystals, while this methodology can be extended to many other bimetallic nanomaterials. [ABSTRACT FROM AUTHOR]

Multiferroics refer to materials with two or more ferroic orders in one phase within a specific temperature range, including ferroelectricity, ferroelasticity, and ferromagnetism which have been widely used in sensors, actuators, and memory devices. Among them, hybrid perovskites exhibiting multiferroicity are generally limited to low dimensions (0D–2D). Designing 3D lead‐free perovskite multiferroics remains a challenge due to Goldschmidt's tolerance factor limitation. Here, a multiferroic perovskite (R‐3AP)RbBr3 (1; 3AP = 3‐ammoniopyrrolidinium) is successfully synthesized by introducing homochirality to the 3D ferroelectric (Rac‐3AP)RbBr3, achieving both ferroelasticity and ferroelectricity. Compound 1 undergoes a structure phase transition at 401 K belonging to Aizu notation 432F2(s), which has 12 ferroelectric equivalent polarization directions and 6 polar axes. Furthermore, 1 exhibits reversible second harmonic generation switching effects. Moreover, while the temperature varies, the reversible and rapid changes of ferroelastic domains in 1 are observed using a polarizing microscope, indicating that it is a ferroelastic material. This work provides a practical method for designing and synthesizing molecule‐based multiferroics. [ABSTRACT FROM AUTHOR]

Shifting from the typical 4e– pathway to H2O in electrochemical oxygen reduction to the 2e– pathway to H2O2 is increasingly recognized as an environmentally friendly approach for producing H2O2. However, the competitive 4e− pathway is a significant obstacle to the production of H2O2 since H2O is the thermodynamically favored product. Here, a series of Pt, Pd, and Rh active atoms diluted within inert‐Au matrices with precisely controlled atomic arrangements and coordination environments are synthesized via facet engineering for O2‐to‐H2O2 production. Surprisingly, individually dispersed Pt atoms within the Au surface enclosed by the square atomic arrangements exhibit superior H2O2 selectivity and achieve a maximum selectivity of 90% at 0.36 V versus the reversible hydrogen electrode. Operando synchrotron ambient pressure X‐ray photoelectron spectroscopy identifies the presence of *OOH key intermediates on these isolated Pt active sites. Grand canonical density‐functional theory also reveals that the kinetic energy barrier for the 2e− pathway (0.08 eV; OOH* + H+ + e− → H2O2) on the isolated Pt sites is significantly lower than the 4e− pathway (0.29 eV; OOH* + H+ + e− → O* + H2O). This work enables atomic‐scale control in dilute binary alloy surfaces with specific configurations of isolated active atoms and provides essential guidance for catalyst design to boost O2‐to‐H2O2 production. [ABSTRACT FROM AUTHOR]

The design of multicomponent materials has captured considerable attention due to its extraordinary ability to tailor functional properties. However, how a single element affects the behavior of the overall material has yet to be explored in depth. In this study, the heteroepitaxy of high entropy (Fe, Co, Ni, Cr, Mn)3O4 films with varying strain states are investigated in magnetic performance. It is discovered that the high entropy oxide thin film with compressive strain exhibits an effect of crystalline magnetic anisotropy. Diverse analyses provide a detailed understanding of high entropy magnetic oxide systems, including X‐ray diffraction, reciprocal space mapping, macroscopic magnetic characterization, X‐ray absorption spectroscopy (XAS), etc. Notably, the element‐specific XAS technique proves effective in uncovering the origin of the crystalline magnetic anisotropy. Due to the substrate‐induced epitaxial strain, the eg orbitals of Mn3+ form different energy levels, leading to different preferred electron occupancy. The exploration of magnetic properties in epitaxial high entropy oxide film is then raveled. By navigating the complexities introduced by the random atom distribution and intricate magnetic interactions, this study pioneers novel methodologies for probing the core physics of high entropy oxides. [ABSTRACT FROM AUTHOR]

High‐performance and long‐term stable self‐powered photodetectors (PDs) based on methylammonium lead iodide nanowires (NWs) are demonstrated by incorporating n‐type conjugated polymer poly{2,5‐bis(2‐dodecylhexadecyl)‐3,6‐di(thiophen‐2‐yl)pyrrolo‐[3,4‐c]pyrrole‐1,4(2H,5H)‐dione‐alt‐(E)‐1,2‐bis(3‐cyanothiophen‐2‐yl)ethene} (DPP‐CNTVT) as multi‐functional interfacial layer. Incorporating DPP‐CNTVT with abundant Lewis base functional groups can effectively passivate under‐coordinated Pb2+ defects, enabling perovskite NWs to exhibit remarkable stability and optoelectronic properties. Meanwhile, high electron mobility, together with the proper energy level of DPP‐CNTVT, makes it ideal for use as an electron transport layer. Particularly, by taking advantage of the low bandgap of DPP‐CNTVT, the utilization of low energy photons can be improved. The resulting PDs exhibit responsivity up to 0.50 A W−1, specific detectivity approaching 1014 Jones, and a wide linear dynamic range of nearly 265 dB under zero bias operation, which represent the best results ever reported for self‐powered perovskite PDs. More encouragingly, with the incorporation of an appropriate encapsulation layer, nearly 90% of the initial detectivity of PDs can be secured after 15 300 h of continuous operation in ambient conditions. The application of NWs PDs for solution‐processed reflective‐mode pulse oximetry is also demonstrated. This study provides valuable insights into developing efficient and ultra‐stable self‐powered perovskite PDs through interfacial engineering, which can accelerate the practical applications of this emerging technology. [ABSTRACT FROM AUTHOR]

Crystalline metal halide perovskites (MHPs) have ushered in remarkable advancements across diverse fields, including materials, electronics, and photonics. While the advantages of crystallinity are well‐established, the ability to transition to a glassy state with unique properties presents unprecedented opportunities to expand the structure‐property relationship and broaden the application scope for 2D MHPs. Up until now, the exploration of amorphous analogs for MHPs is confined to high‐pressure conditions, limiting in‐depth studies and practical applications. In this context, a new type of 2D MHPs is synthesized by incorporating halogen substituted organic cations, resulting in a remarkable combination of low melting temperature and inhibited crystallization. This new type of 2D MHPs can be effectively melt‐quenched into a glassy state except for (DMIEA)3Pb2I7 (DMIEA = N, N‐dimethyl iodoethylammonium) counterpart. Analysis of the crystallization activation energy for (DMIPA)4Pb3I10 (DMIPA = N, N‐dimethyl iodopropylammonium) reveals a low crystallization activation energy of 60.7 ± 4.0 kJ mol−1, which indicates a fast glass‐crystal transition. The type of atypical 2D MHP showcases facile and reversible switching between glassy and crystalline states and opens up novel possibilities for applications, such as nonvolatile memory, optical communication, and neuromorphic computing. [ABSTRACT FROM AUTHOR]

Searching the high-efficient, stable, and earth-abundant electrocatalysts to replace the precious noble metals holds the promise for practical utilizations of hydrogen and oxygen evolution reactions (HER and OER). Here, a series of highly active and robust Co-doped nickel phosphides (Ni2− xCo xP) catalysts and their hybrids with reduced graphene oxide (rGO) are developed as bifunctional catalysts for both HER and OER. The Co-doping in Ni2P and their hybridization with rGO effectively regulate the catalytic activity of the surface active sites, accelerate the charge transfer, and boost their superior catalytic activity. Density functional theory calculations show that the Co-doped catalysts deliver the moderate trapping of atomic hydrogen and facile desorption of the generated H2 due to the H-poisoned surface active sites of Ni2− xCo xP under the real catalytic process. Electrochemical measurements reveal the high HER efficiency and durability of the NiCoP/rGO hybrids in electrolytes with pH 0-14. Coupled with the remarkable and robust OER activity of the NiCoP/rGO hybrids, the practical utilization of the NiCoP/rGO|NiCoP/rGO for overall water splitting yields a catalytic current density of 10 mA cm−2 at 1.59 V over 75 h without an obvious degradation and Faradic efficiency of ≈100% in a two-electrode configuration and 1.0 m KOH. [ABSTRACT FROM AUTHOR]

Integrating multiple switching behaviors in a single material is conducive to the development of smart devices, but still faces challenges, especially in finding new types of multiresponsive materials. Hybrid metal halides have been becoming promising candidates with the potential to exhibit changes in various physical and chemical properties upon structural phase transitions. Herein, a pair of enantiomers (R/S‐3‐OHPD)PbI3 (1R/1S; 3‐HOPD = 3‐hydroxypiperidine cation) is reported to show multichannel switching behaviors around room temperature triggered by a combined order‐disorder and displacive type phase transition that arouses a large lattice reorganization and shape change of the crystals. Owing to the inherent chiral, noncentrosymmetric, and semiconducting characteristics of the compounds, five other switching behaviors are realized besides the macroscopic deformation, that is, enthalpy, dielectric permittivity, photoluminescence, circularly polarized light excited photoluminescence, and photoelectric response. This study provides an exciting example of phase transition crystals for the development of integrated multifunctional materials. [ABSTRACT FROM AUTHOR]

Decellularized small intestine submucosa (dSIS) is a promising biomaterial for promoting tissue regeneration. Isolated from the submucosal layer of animal jejunum, SIS is rich in extracellular matrix (ECM) proteins, including collagen, laminin, and fibronectin. Following mild decellularization, dSIS becomes an acellular matrix that supports cell adhesion, proliferation, and differentiation. Conventional dSIS matrix is usually obtained by thermal crosslinking, which yields a soft scaffold with low stability. To address these challenges, dSIS is modified with methacrylate groups for photocrosslinking into stable hydrogels. However, dSIS has not been modified with clickable handles for orthogonal crosslinking. Here, the development of norbornene‐modified dSIS, named dSIS‐NB, via reacting amine groups of dSIS with carbic anhydride in acidic aqueous reaction conditions is reported. Using triethylamine (TEA) as a mild base catalyst, high degrees of NB substitution on dSIS are obtained. In addition to describing the synthesis of dSIS‐NB, its adaptability in orthogonal hydrogel crosslinking for cancer and vascular tissue engineering is explored. Impressively, compared with physically crosslinked dSIS and collagen matrices, orthogonally crosslinked dSIS‐NB hydrogels supported rapid dissemination of cancer cells and superior vasculogenic and angiogenic properties. dSIS‐NB is also exploited as a versatile bioink for 3D bioprinting. [ABSTRACT FROM AUTHOR]