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Exploring structural phase transitions and luminescence mechanisms in zero‐dimensional (0D) metal halides poses significant challenges, that are crucial for unlocking the full potential of tunable optical properties and diversifying their functional capabilities. Herein, we have designed two inter‐transformable 0D Cu(I)‐based metal halides, namely (C19H18P)2CuI3 and (C19H18P)2Cu4I6, through distinct synthesis conditions utilizing identical reactants. Their optical properties and luminescence mechanisms were systematically elucidated by experiments combined with density functional theory calculations. The bright cyan‐fluorescent (C19H18P)2CuI3 with high photoluminescence quantum yield (PLQY) of 77 % is attributed to the self‐trapped exciton emission. Differently, the broad yellow‐orange fluorescence of (C19H18P)2Cu4I6 displays a remarkable PLQY of 83 %. Its luminescence mechanism is mainly attributed to the combined effects of metal/halide‐to‐ligand charge transfer and cluster‐centered charge transfer, which effects stem from the strong Cu−Cu bonding interactions in the (Cu4I6)2− clusters. Moreover, (C19H18P)2CuI3 and (C19H18P)2Cu4I6 exhibit reversible structural phase transitions. The elucidation of the phase transitions mechanism has paved the way for an unforgeable anti‐counterfeiting system. This system dynamically shifts between cyan and yellow‐orange fluorescence, triggered by the phase transitions, bolstering security and authenticity. This work enriches the luminescence theory of 0D metal halides, offering novel strategies for optical property modulation and fostering optical applications. [ABSTRACT FROM AUTHOR]

Photothermal therapy (PTT) stimulated by light in the second near-infrared (NIR-II) biowindow shows great superiorities in the penetration ability of tissue and maximum permissible exposure (MPE). Exploring new photothermal agents with good optical absorbance in the NIR-II region is highly desirable for efficient cancer therapy. Herein, we successfully prepare carambola-like bismuth telluride (Bi2Te3) superstructures modified with PEGylated phospholipid (Bi2Te3@PEG) for CT imaging-guided PTT in the NIR-II biowindow. Attributing to their superstructures, Bi2Te3@PEG exhibited enhanced photoabsorption with higher photothermal conversion efficiency (55.3% for 1064 nm) compared with that of Bi2Te3 nanoparticles. Furthermore, the good X-ray attenuation capacity of Bi endows Bi2Te3@PEG with an outstanding performance as computed tomography (CT) contrast agents. Bi2Te3@PEG superstructures have been confirmed to effectively eliminate tumor in vitro and in vivo with negligible long-term toxicities, offering them great potential to act as theranostic platforms for cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) are promising cathode materials for supercapacitors because of the enhanced flow efficiency of ions in the interlayers. However, the limited active sites and monotonous metal species further hinder the improvement of the capacity performance. Herein, cobalt sulfide quantum dots (Co9S8‐QDs) are effectively created and embedded within the interlayer of metal‐organic‐frameworks‐derived ternary metal LDH nanosheets based on in situ selective vulcanization of Co on carbon fibers. The hybrid CF@NiCoZn‐LDH/Co9S8‐QD retains the lamellar structure of the ternary metal LDH very well, inheriting low transfer impedance of interlayer ions. Significantly, the selectively generated Co9S8‐QDs expose more abundant active sites, effectively improving the electrochemical properties, such as capacitive performance, electronic conductivity, and cycling stability. Due to the synergistic relationship, the hybrid material delivers an ultrahigh electrochemical capacity of 350.6 mAh g−1 (2504 F g−1) at 1 A g−1. Furthermore, hybrid supercapacitors fabricated with CF@NiCoZn‐LDH/Co9S8‐QD and carbon nanosheets modified by single‐walled carbon nanotubes display an outstanding energy density of 56.4 Wh kg−1 at a power density of 875 W kg−1, with an excellent capacity retention of 95.3% after 8000 charge–discharge cycles. Therefore, constructing hybrid electrode materials by in situ‐created QDs in multimetallic LDHs is promising. [ABSTRACT FROM AUTHOR]

A robust self‐template strategy is used for facile and large‐scale synthesis of porous multishell gold with controllable shell number, sphere size, and in situ surface modification. The process involved the rapid reduction of novel Au‐melamine colloidal templates with a great amount of NaBH4 in presence of poly(sodium‐p‐styrenesulfonate) (PSS). After soaking the templates in other metal salt solution, the obtained bimetallic templates could also be generally converted into bimetallic multishell structures by same reduction process. In the hydrogenation of 4‐nitrostyrene using NH3BH3 as a reducing agent, the porous triple‐shell Au with surface modification (S‐PTSAu) exhibited excellent selectivity (97 %) for 4‐aminostyrene in contrast with unmodified triple‐shell Au. Furthermore, it also showed higher enhancement of catalytic activity under irradiation of visible light as compared to similar catalysts with fewer shells. [ABSTRACT FROM AUTHOR]

A CeO2-supported Au nanohybrid is regarded as a promising catalytic system for CO oxidation, but its unsatisfactory catalytic activity and high cost are still challenges for sustainable application. In this work, we have synthesized a series of low loading and high activity Au/CeO2 supported catalysts using a coprecipitation method. Au/CeO2 catalysts with a low Au content (0.2 wt%) showed extremely high activity for CO oxidation with 100% conversion of CO around 60 °C. The key to the success is that the unique oxygen-deficient structure of cerium oxide can capture gold to provide a strong synergistic effect between the metal and the support. The content of gold in their oxidation states (Au+1, Au+3) present in the catalyst is one of the important factors affecting the catalytic activity. Furthermore, all of the prepared catalysts present a high BET surface area of roughly 140 m2 g−1. This high specific surface area provides adequate adsorption sites for CO. Moreover, the low loading of Au is critical to reducing the cost of noble metal-based catalysts and making them practical for industrial applications. [ABSTRACT FROM AUTHOR]

The Pt-Ni nanoframe catalysts have attracted great interest owing to their unique electronic structure and excellent catalytic performance. However, the stability of the tenuous edges of nanoframe-structures is dissatisfactory and their universal applications in catalytic market beyond electrocatalytic reactions are yet to be tapped and explored. Herein, we developed a new core@shell structured Pt-Ni nanoframe@CeO2 (Pt-Ni NF@CeO2) composite via etching the Ni from inhomogeneous Pt-Ni rhombic dodecahedra (Pt-Ni RD) by cerium(III) acetate hydrate (Ce(OAc)3). In this path, Pt-Ni RD was used as self-sacrificial template, while the Ce(OAc)3 serves as the provider of the Ce3+ source and OH− for the formation of CeO2 shell, etchant of Pt-Ni RD, and the surface modification agent. By this way, the etching of Pt-Ni RD and the formation of the CeO2 shell are simultaneously proceeded to form the final Pt-Ni NF@CeO2 in one step. The obtained Pt-Ni NF@CeO2 exhibits strong interfacial charge transfer interaction between Pt-Ni NF core and CeO2 shell even without reduction treatment, leading to enhanced catalytic activity in the hydrogenation of phenylacetylene. After introduction of trace silver, the Pt-Ni-Ag4.9 NF@CeO2 achieves remarkable catalytic performance for the selective conversion of phenylacetylene to styrene: high conversion (100%), styrene selectivity (86.5%), and good stability. It reveals that encapsulation noble metal nanoframes into metal oxide to form core@shell structured hybrids will indeed enhance their stability and catalytic properties. Particularly, this work expends the application of noble metal nanoframes materials to hydrogenation reactions. [ABSTRACT FROM AUTHOR]

High‐quality (Pd cube)@(Pt helix) core@shell nanoparticles, with a novel spiral‐structured shell and highly‐ordered tangential channels are successfully fabricated through a facile wet chemistry method with the help of N,N‐dimethyloctadecyl ammonium bromide acetate sodium (OTAB‐Na). A bottom‐up synthesis strategy provides accurate control of layers by simply changing the molar ratio of Pt/Pd with a uniform layer thickness of 2 nm maintained in all (1–3)‐rounds samples. The irregular Pt superstructures of the shells, and sophisticated core@shell hybrid materials endow the as‐produced samples with highly enhanced catalytic properties, when evaluated for hydrogenation of nitrobenzene as a probe reaction. Shell game: Spiral‐structured Pt shells with highly‐ordered tangential channels are successfully fabricated in Pd@Pt core@shell nanoparticles through kinetic control with the aid of a novel surfactant. Eventually, the number of layers can be easily tuned by the changing the molar ratio of Pt/Pd while uniform layer thickness and cubic Pd core maintained. [ABSTRACT FROM AUTHOR]

Abstract: Bi2Te3 hierarchical nanostrings have been synthesized through a solvothermal approach with the assistance of sucrose. The hierarchical Bi2Te3 was supposed to be fabricated through a self‐assembly process. Te nanorods first emerge with the reduction of TeO32− followed by heterogeneous nucleation of Bi2Te3 nanoplates on the surface and tips of Te nanorods. Te nanorods further transform into Bi2Te3 nanorods simultaneously with the nanoplates’ growth leading to a hierarchical structure. By controlling the reaction kinetics by adding different amount of ethylene glycol, the length of nanorods and the number of nanoplates could be tailored. The use of sucrose is vital to the formation of hierarchical structure because it not only serves as a template for the well‐defined growth of Te nanorods but also promotes the heterogeneous nucleation of Bi2Te3 in the self‐assembly process. The Bi2Te3 nanomaterial shows a moderate thermoelectric performance because of its hierarchical structure. This study shows a promising way to synthesize Bi2Te3‐based nanostructures through environmental friendly approach. [ABSTRACT FROM AUTHOR]

Nickel-based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self-oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru-Co dual-atom support (Ru-Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru-Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm -2 and remarkable long-term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR., (© 2023 Wiley-VCH GmbH.)