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Inorganic solid‐state electrolytes (SSEs) play a vital role in high‐energy all‐solid‐state batteries (ASSBs). However, the current method of SSE preparation usually involves high‐energy mechanical ball milling and/or a high‐temperature annealing process, which is not suitable for practical application. Here, a facile strategy is developed to realize the scalable synthesis of cost‐effective aluminum‐based oxyhalide SSEs, which involves a self‐propagating method by the exothermic reaction of the raw materials. This strategy enables the synthesis of various aluminum‐based oxyhalide SSEs with tunable components and high ionic conductivities (over 10−3 S cm−1 at 25 °C) for different cations (Li+, Na+, Ag+). It is elucidated that the amorphous matrix, which mainly consists of various oxidized chloroaluminate species that provide numerous sites for smooth ion migration, is actually the key factor for the achieved high conductivities. Benefit from their easy synthesis, low cost, and low weight, the aluminum‐based oxyhalide SSEs synthesized by our approach could further promote practical application of high‐energy‐density ASSBs. [ABSTRACT FROM AUTHOR]

Crystalline frameworks represent a cutting‐edge frontier in material science, and recently, there has been a surge of interest in energetic crystalline frameworks. However, the well‐established porosity often leads to diminished output energy, necessitating a novel approach for performance enhancement. Thiol‐yne coupling, a versatile metal‐free click reaction, has been underutilized in crystalline frameworks. As a proof of concept, we herein demonstrate the potential of this approach by introducing the energy‐rich, size‐matched, and reductive 1,2‐dicarbadodecaborane‐1‐thiol (CB−SH) into an acetylene‐functionalized framework, Zn(AIm)2, via thiol‐yne click reaction. This innovative decoration strategy resulted in a remarkable 46.6 % increase in energy density, a six‐fold reduction in ignition delay time (4 ms) with red fuming nitric acid as the oxidizer, and impressive enhancement of stability. Density functional theory calculations were employed to elucidate the mechanism by which CB−SH promotes hypergolic ignition. The thiol‐yne click modification strategy presented here permits engineering of crystalline frameworks for the design of advanced energetic materials. [ABSTRACT FROM AUTHOR]

As exciting candidates for next‐generation energy storage, all‐solid‐state lithium batteries (ASSLBs) are highly dependent on advanced solid‐state electrolytes (SSEs). Here, using cost‐effective LaCl3 and CeCl3 lattice (UCl3‐type structure) as the host and further combined with a multiple‐cation mixed strategy, we report a series of UCl3‐type SSEs with high room‐temperature ionic conductivities over 10−3 S cm−1 and good compatibility with high‐voltage oxide cathodes. The intrinsic large‐size hexagonal one‐dimensional channels and highly disordered amorphous phase induced by multi‐metal cation species are believed to trigger fast multiple ionic conductions of Li+, Na+, K+, Cu+, and Ag+. The UCl3‐type SSEs enable a stable prototype ASSLB capable of over 3000 cycles and high reversibility at −30 °C. Further exploration of the brand‐new multiple‐cation mixed chlorides is likely to lead to the development of advanced halide SSEs suitable for ASSLBs with high energy density. [ABSTRACT FROM AUTHOR]

Classical electrochemical characterization tools cannot avoid averaging between the active reaction sites and their support, thus obscuring their intrinsic roles. Single‐molecule electrochemical techniques are thus in high demand. Here, we demonstrate super‐resolution imaging of Ru(bpy)32+ based reactions on Au plates using single‐molecule electrochemiluminescence microscopy. By converting electrochemical signals into optical signals, we manage to achieve the ultimate sensitivity of single‐entity chemistry, that is directly resolving the single photons from individual electrochemical reactions. High spatial resolution, up to 37 nm, further enables mapping Au chemical activity and the reaction kinetics. The spatiotemporally resolved dynamic structure–activity relationship on Au plates shows that the restructuring of catalysts plays an important role in determining the reactivity. Our approach may lead to gaining new insights towards evaluating and designing electrocatalytic systems. [ABSTRACT FROM AUTHOR]

An asymmetric allylic C−H functionalization has been developed by making use of transient chiral nucleophiles, as well as bimetallic synergistic catalysis with an achiral Pd0catalyst and a chiral N,N′‐dioxide‐CoIIcomplex. A variety of β‐ketoesters and N‐Boc oxindoles coupled with allylbenzenes and aliphatic terminal alkenes were well tolerated, furnishing the desired allylic alkylation products in high yields (up to 99 %) with excellent regioselectivities and enantioselectivities (up to 99 % ee). [ABSTRACT FROM AUTHOR]

It is an ongoing challenge to design and synthesize magnetic materials that undergo colossal thermal expansion and that possess potential applications as microscale or nanoscale actuators with magnetic functionality. A paramagnetic metallocyanate building block was used to construct a cyanide-bridged Fe-Co complex featuring both positive and negative colossal volumetric thermal-expansion behavior. A detailed study revealed that metal-to-metal charge transfer between 180 and 240 K induced a volumetric thermal expansion coefficient of 1498 MK−1 accompanied with hysteretic spin transition. Rotation of the magnetic building blocks induced change of π⋅⋅⋅π interactions, resulting in a negative volume expansion coefficient of −489 MK−1, and another hysteretic magnetic transition between 300 and 350 K. This work presents a strategy for incorporating both colossal positive and negative volumetric thermal expansion with shape and magnetic memory effects in a material. [ABSTRACT FROM AUTHOR]

Double hydrosilylation of alkynes represents a straightforward method to synthesize bis(silane)s, yet it is challenging if α‐substituted vinylsilanes act as the intermediates. Here, a cobalt‐catalyzed regiodivergent double hydrosilylation of arylacetylenes is reported for the first time involving this challenge, accessing both vicinal and geminal bis(silane)s with exclusive regioselectivity. Various novel bis(silane)s containing Si−H bonds can be easily obtained. The gram‐scale reactions could be performed smoothly. Preliminarily mechanistic studies demonstrated that the reactions were initiated by cobalt‐catalyzed α‐hydrosilylation of alkynes, followed by cobalt‐catalyzed β‐hydrosilylation of the α‐vinylsilanes to deliver vicinal bis(silane)s, or hydride‐catalyzed α‐hydrosilylation to give geminal ones. Notably, these bis(silane)s can be used for the synthesis of high‐refractive‐index polymers (nd up to 1.83), demonstrating great potential utility in optical materials. [ABSTRACT FROM AUTHOR]

The utilization of oxygen vacancies (OVs) in sodium ion batteries (SIBs) is expected to enhance performance, but as yet it has rarely been reported. Taking the MoO3− x nanosheet anode as an example, for the first time we demonstrate the benefits of OVs on SIB performance. Moreover, the benefits at deep-discharge conditions can be further promoted by an ultrathin Al2O3 coating. A series of measurements show that the OVs increase the electric conductivity and Na-ion diffusion coefficient, and the promotion from ultrathin coating lies in the effective reduction of cycling-induced solid-electrolyte interphase. The coated nanosheets exhibited high reversible capacity and great rate capability with the capacities of 283.9 (50 mA g−1) and 179.3 mAh g−1 (1 A g−1) after 100 cycles. This work may not only arouse future attention on OVs for sodium energy storage, but also open up new possibilities for designing strategies to utilize defects in other energy storage systems. [ABSTRACT FROM AUTHOR]

Light-harvesting and charge collection have attracted increasing attention in the domain of photovoltaic cells, and can be facilitated dramatically by appropriate design of a photonic nanostructure. However, the applicability of current light-harvesting photoanode materials with single component and/or morphology (such as, particles, spheres, wires, sheets) is still limited by drawbacks such as insufficient electron-hole separation and/or light-trapping. Herein, we introduce a universal method to prepare hierarchical assembly of macroporous material-nanowire coated homogenous or heterogeneous metal oxide composite electrodes (TiO2-TiO2, SnO2-TiO2, and Zn2SnO4-TiO2; homogenous refers to a material in which the nanowire and the macroporous material have the same composition, i.e. both are TiO2. Heterogeneous refers to a material in which the nanowires and the macroporous material have different compositions). The dye-sensitized solar cell based on a TiO2-macroporous material-TiO2-nanowire homogenous composition electrode shows an impressive conversion efficiency of 9.51 %, which is much higher than that of pure macroporous material-based photoelectrodes to date. [ABSTRACT FROM AUTHOR]

An asymmetric allylic C−H functionalization has been developed by making use of transient chiral nucleophiles, as well as bimetallic synergistic catalysis with an achiral Pd0 catalyst and a chiral N,N′‐dioxide‐CoII complex. A variety of β‐ketoesters and N‐Boc oxindoles coupled with allylbenzenes and aliphatic terminal alkenes were well tolerated, furnishing the desired allylic alkylation products in high yields (up to 99 %) with excellent regioselectivities and enantioselectivities (up to 99 % ee). [ABSTRACT FROM AUTHOR]

Nitrogen‐heterocycle‐based covalent organic frameworks (COFs) are considered promising candidates for the overall photosynthesis of hydrogen peroxide (H2O2). However, the effects of the relative nitrogen locations remain obscured and photocatalytic performances of COFs need to be further improved. Herein, a collection of COFs functionalized by various diazines including pyridazine, pyrimidine, and pyrazine have been judiciously designed and synthesized for photogeneration of H2O2 without sacrificial agents. Compared with pyrimidine and pyrazine, pyridazine embedded in TpDz tends to stabilize endoperoxide intermediate species, leading toward the more efficient direct 2e‐ oxygen reduction reaction (ORR) pathway. Benefiting from the effective electron‐hole separation, low charge transfer resistance, and high‐efficiency ORR pathway, an excellent production rate of 7327 μmol g−1 h−1 and a solar‐to‐chemical conversion (SCC) value of 0.62 % has been achieved by TpDz, which ranks one of the best COF‐based photocatalysts. This work might shed fresh light on the rational design of functional COFs targeting photocatalysts in H2O2 production. [ABSTRACT FROM AUTHOR]

Two‐photon‐excited photodynamic therapy (TPE‐PDT) has significant advantages over conventional photodynamic therapy (PDT). However, obtaining easily accessible TPE photosensitizers (PSs) with high efficiency remains a challenge. Herein, we demonstrate that emodin (Emo), a natural anthraquinone (NA) derivative, is a promising TPE PS with a large two‐photon absorption cross‐section (TPAC: 380.9 GM) and high singlet oxygen (1O2) quantum yield (31.9 %). When co‐assembled with human serum albumin (HSA), the formed Emo/HSA nanoparticles (E/H NPs) possess a giant TPAC (4.02×107 GM) and desirable 1O2 generation capability, thus showing outstanding TPE‐PDT properties against cancer cells. In vivo experiments reveal that E/H NPs exhibit improved retention time in tumors and can ablate tumors at an ultra‐low dosage (0.2 mg/kg) under an 800 nm femtosecond pulsed laser irradiation. This work is beneficial for the use of natural extracts NAs for high‐efficiency TPE‐PDT. [ABSTRACT FROM AUTHOR]

Cobalt ferrite (CoFe2O4) spinel has been found to produce C2−C4 hydrocarbons in a single‐step, ambient‐pressure, photocatalytic hydrogenation of CO2 with a rate of 1.1 mmol g−1 h−1, selectivity of 29.8 % and conversion yield of 12.9 %. On stream the CoFe2O4 reconstructs to a CoFe−CoFe2O4 alloy‐spinel nanocomposite which facilitates the light‐assisted transformation of CO2 to CO and hydrogenation of the CO to C2−C4 hydrocarbons. Promising results obtained from a laboratory demonstrator bode well for the development of a solar hydrocarbon pilot refinery. [ABSTRACT FROM AUTHOR]

The bottom‐up preparation of two‐dimensional material micro‐nano structures at scale facilitates the realisation of integrated applications in optoelectronic devices. Fibrous Phosphorus (FP), an allotrope of black phosphorus (BP), is one of the most promising candidate materials in the field of optoelectronics with its unique crystal structure and properties.[1] However, to date, there are no bottom‐up micro‐nano structure preparation methods for crystalline phosphorus allotropes.[1c, 2] Herein, we present the bottom‐up preparation of fibrous phosphorus micropillar (FP‐MP) arrays via a low‐pressure gas‐phase transport (LP‐CVT) method that controls the directional phase transition from amorphous red phosphorus (ARP) to FP. In addition, self‐powered photodetectors (PD) of FP‐MP arrays with pyro‐phototronic effects achieved detection beyond the band gap limit. Our results provide a new approach for bottom‐up preparation of other crystalline allotropes of phosphorus. [ABSTRACT FROM AUTHOR]

Nucleic acid (NA) computation has been widely developed in the past years to solve kinds of logic and mathematic issues in both information technologies and biomedical analysis. However, the difficulty to integrate non‐NA molecules limits its power as a universal platform for molecular computation. Here, we report a versatile prototype of hybridized computation integrated with both nucleic acids and non‐NA molecules. Employing the conformationally controlled ligand converters, we demonstrate that non‐NA molecules, including both small molecules and proteins, can be computed as nucleic acid strands to construct the circuitry with increased complexity and scalability, and can be even programmed to solve arithmetical calculations within the computational nucleic acid system. This study opens a new door for molecular computation in which all‐NA circuits can be expanded with integration of various ligands, and meanwhile, ligands can be precisely programmed by the nuclei acid computation. [ABSTRACT FROM AUTHOR]

Probing proton transport is of vital importance for understanding cellular transport, surface catalysis and fuel cells. Conventional proton transport measurements rely on the use of electrochemical conductivity and do not allow for the direct visualization of proton transport pathways. The development of novel experimental techniques to spatiotemporally resolve proton transport is in high demand. Here, building upon the general conversion of aqueous proton flux into spatially resolved fluorescence signals, we optically visualize proton transport through nanopores and along hydrophilic interfaces. We observed that the fluorescence intensity increased at negative voltage due to lateral transport. Thanks to the temporal resolution of optical imaging, our technique further empowers the analysis of proton transport dynamics. [ABSTRACT FROM AUTHOR]

The performances of electron‐transport‐layer (ETL)‐free perovskite solar cells (PSCs) are still inferior to ETL‐containing devices. This is mainly due to severe interfacial charge recombination occurring at the transparent conducting oxide (TCO)/perovskite interface, where the photo‐injected electrons in the TCO can travel back to recombine with holes in the perovskite layer. Herein, we demonstrate for the first time that a non‐annealed, insulating, amorphous metal oxyhydroxide, atomic‐scale thin interlayer (ca. 3 nm) between the TCO and perovskite facilitates electron tunneling and suppresses the interfacial charge recombination. This largely reduced the interfacial charge recombination loss and achieved a record efficiency of 21.1 % for n‐i‐p structured ETL‐free PSCs, outperforming their ETL‐containing metal oxide counterparts (18.7 %), as well as narrowing the efficiency gap with high‐efficiency PSCs employing highly crystalline TiO2 ETLs. [ABSTRACT FROM AUTHOR]

Vacancy engineering has been proved repeatedly as an adoptable strategy to boost electrocatalysis, while its poor selectivity restricts the usage in nitrogen reduction reaction (NRR) as overwhelming competition from hydrogen evolution reaction (HER). Revealed by density functional theory calculations, the selenium vacancy in ReSe2 crystal can enhance its electroactivity for both NRR and HER by shifting the d‐band from −4.42 to −4.19 eV. To restrict the HER, we report a novel method by burying selenium vacancy‐rich ReSe2@carbonized bacterial cellulose (Vr‐ReSe2@CBC) nanofibers between two CBC layers, leading to boosted Faradaic efficiency of 42.5 % and ammonia yield of 28.3 μg h−1 cm−2 at a potential of −0.25 V on an abrupt interface. As demonstrated by the nitrogen bubble adhesive force, superhydrophilic measurements, and COMSOL Multiphysics simulations, the hydrophobic and porous CBC layers can keep the internal Vr‐ReSe2@CBC nanofibers away from water coverage, leaving more unoccupied active sites for the N2 reduction (especially for the potential determining step of proton‐electron coupling and transferring processes as *NN → *NNH). [ABSTRACT FROM AUTHOR]

An unprecedented approach for efficient synthesis of functionalized allylic gem‐difluorides via catalytic fluorinative Meyer–Schuster‐like rearrangement is disclosed. This transformation proceeded with readily accessible propargylic fluorides, and low‐cost B–F reagents and electrophilic reagents by sulfide catalysis. A series of iodinated, brominated, and trifluoromethylthiolated allylic gem‐difluorides that were difficult to access by other methods were facilely produced with a wide range of functional groups. Importantly, the obtained iodinated products could be incorporated into different drugs and natural products, and could be expediently converted into many other valuable gem‐difluoroalkyl molecules as well. Mechanistic studies revealed that this reaction went through a regioselective fluorination of alkynes followed by a formal 1,3‐fluorine migration under the assistance of the B–F reagents to give the desired products. [ABSTRACT FROM AUTHOR]

Latent O‐glycosides, 2‐(2‐propylthiol)benzyl (PTB) glycosides, were converted into the corresponding active glycosyl donors, 2‐(2‐propylsulfinyl)benzyl (PSB) glycosides, by a simple and efficient oxidation. Treatment of the PSB donor and various acceptors with triflic anhydride provided the desired glycosides in good to excellent yields. The leaving group, which was activated by an interrupted Pummerer reaction, can be recycled (PSB‐OH) and regenerated as the precursor (PTB‐OH). A natural hepatoprotective glycoside, leonoside F, was efficiently synthesized in a convergent [3+1] manner with this newly developed method. The present total synthesis also led to a structural revision of this phenylethanoid glycoside.Actively latent: An efficient glycosylation enabled by an interrupted Pummerer reaction was successfully achieved. The active glycosyl donor possessing a recyclable and regenerative leaving group was obtained from a simple oxidation of the corresponding latent precursor. This strategy allowed the total synthesis and structural revision of the natural product leonoside F. [ABSTRACT FROM AUTHOR]