Axially Modified Square-Pyramidal CoN-F Sites Enabling High-Performance Zn-Air Batteries.

Cobalt-nitrogen-carbon (Co-N-C) catalysts with a CoN structure exhibit great potential for oxygen reduction reaction (ORR), but the imperfect adsorption energy toward oxygen species greatly limits their reduction efficiency and practical application potential. Here, F-coordinated Co-N-C catalysts with square-pyramidal CoN-F configuration are successfully synthesized using F atoms to regulate the axial coordination of Co centers via hydrothermal and chemical vapor deposition methods. During the synthesis process, the geometry structure of the Co atom converts from six-coordinated Co-F to square-pyramidal CoN-F in the coordinatively unsaturated state, which provides an open binding site for the O.

Nanocurvature-induced field effects enable control over the activity of single-atom electrocatalysts.

Tuning interfacial electric fields provides a powerful means to control electrocatalyst activity. Importantly, electric fields can modify adsorbate binding energies based on their polarizability and dipole moment, and hence operate independently of scaling relations that fundamentally limit performance. However, implementation of such a strategy remains challenging because typical methods modify the electric field non-uniformly and affects only a minority of active sites.

In-Plane Topological-Defect-Enriched Graphene as an Efficient Metal-Free Catalyst for pH-Universal HO Electrosynthesis.

Developing efficient metal-free catalysts to directly synthesize hydrogen peroxide (HO) through a 2-electron (2e) oxygen reduction reaction (ORR) is crucial for substituting the traditional energy-intensive anthraquinone process. Here, in-plane topological defects enriched graphene with pentagon-S and pyrrolic-N coordination (SNC) is synthesized via the process of hydrothermal and nitridation. In SNC, pentagon-S and pyrrolic-N originating from thiourea precursor are covalently grafted onto the basal plane of the graphene framework, building unsymmetrical dumbbell-like S─C─N motifs, which effectively modulates atomic and electronic structures of graphene.

Amorphous Oxyhalide Matters for Achieving Lithium Superionic Conduction.

The recently surged halide-based solid electrolytes (SEs) are great candidates for high-performance all-solid-state batteries (ASSBs), due to their decent ionic conductivity, wide electrochemical stability window, and good compatibility with high-voltage oxide cathodes. In contrast to the crystalline phases in halide SEs, amorphous components are rarely understood but play an important role in Li-ion conduction. Here, we reveal that the presence of amorphous component is common in halide-based SEs that are prepared via mechanochemical method.

Cubic Iodide Li YI Superionic Conductors through Defect Manipulation for All-Solid-State Li Batteries.

Halide solid electrolytes (SEs) have attracted significant attention due to their competitive ionic conductivity and good electrochemical stability. Among typical halide SEs (chlorides, bromides, and iodides), substantial efforts have been dedicated to chlorides or bromides, with iodide SEs receiving less attention. Nevertheless, compared with chlorides or bromides, iodides have both a softer Li sublattice and lower reduction limit, which enable iodides to possess potentially high ionic conductivity and intrinsic anti-reduction stability, respectively.

Xenobiotic Bi Coordination by Cysteine-Rich Metallothionein-3 Reveals a Cooperatively Formed Thiolate-Sharing BiS Cluster.

The field of designing artificial metalloproteins has yet to effectively tackle the incorporation of multimetal clusters, which is a key component of natural metalloproteins, such as metallothioneins (MTs) and calmodulin. MT is a physiological, essential, cysteine-rich metalloprotein that binds to a variety of metals but is only known to form metal-thiolate clusters with Cd, Zn, and Cu. Bismuth is a xenobiotic metal and a component of metallodrugs used to treat gastric ulcers and cancer, as well as an emerging metal used in industrial practices.

A family of oxychloride amorphous solid electrolytes for long-cycling all-solid-state lithium batteries.

Solid electrolyte is vital to ensure all-solid-state batteries with improved safety, long cyclability, and feasibility at different temperatures. Herein, we report a new family of amorphous solid electrolytes, xLiO-MCl (M = Ta or Hf, 0.8 ≤ x ≤ 2, y = 5 or 4).

Structural and optical characterisation of silanised Dy-doped-GdO NPs.

In this work, we studied the optical properties of Dy-doped GdO nanoparticles (NPs) before and after their APTES functionalisation. We obtained luminescent Dy@GdO NPs (0.5, 1, and 5% mol) using a modified polyol method.

The Role of Bismuth in Suppressing the CO Poisoning in Alkaline Methanol Electrooxidation: Switching the Reaction from the CO to Formate Pathway.

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OH) on the catalyst surface.

Superionic Conducting Halide Frameworks Enabled by Interface-Bonded Halides.

The revival of ternary halides Li-M-X (M = Y, In, Zr, etc.; X = F, Cl, Br) as solid-state electrolytes (SSEs) shows promise in realizing practical solid-state batteries due to their direct compatibility toward high-voltage cathodes and favorable room-temperature ionic conductivities. Most of the reported superionic halide SSEs have a structural pattern of [MCl] octahedra and generate a tetrahedron-assisted Li ion diffusion pathway.

The synergetic effect of a gold nanocluster-calcium phosphate composite: enhanced photoluminescence intensity and superior bioactivity.

Gold nanoclusters (AuNCs) are a unique class of materials that exhibit visible luminescence. Amorphous calcium phosphate (ACP) is a widely used biomaterial for a variety of purposes, such as drug delivery, bone cementing, and implant coatings. In this study, a nanocomposite of AuNCs and ACP is prepared by biomimetic mineralization in a Dulbecco's modified Eagle's medium (DMEM).

Surface Defect Engineering of a Bimetallic Oxide Precatalyst Enables Kinetics-Enhanced Lithium-Sulfur Batteries.

Developing efficient electrocatalysts to accelerate the sluggish conversion of lithium polysulfides (LiPSs) is of paramount importance for improving the performances of lithium-sulfur (Li-S) batteries. However, a consensus has not yet been reached on the in situ evolution of the electrocatalysts as well as the real catalytic active sites. Herein, defective MnVO (D-MVO) is designed as a precatalyst toward LiPSs' adsorption and conversion.

Synthesis and characterization of a near-infrared persistent luminescent Cr-doped zinc gallate-calcium phosphate composite.

Near-infrared (NIR)-emitting persistent luminescence (PersL) nanoparticles have attracted great attention as a novel optical probe for bioimaging and biosensing applications. These nanoparticles emit long-lasting luminescence after the removal of the excitation source, which effectively eliminates the interference from tissue autofluorescence. Cr-doped zinc gallate (ZnGaO:Cr, CZGO) is a representative NIR-emitting PersL material.

Boosting the Cycling Stability of Aqueous Zinc-Ion Batteries through Nanofibrous Coating of a Bead-like MnO Cathode.

Rechargeable aqueous zinc-ion batteries (AZIBs) are close complements to lithium-ion batteries for next-generation grid-scale applications owing to their high specific capacity, low cost, and intrinsic safety. Nevertheless, the viable cathode materials (especially manganese oxides) of AZIBs suffer from poor conductivity and inferior structural stability upon cycling, thereby impeding their practical applications. Herein, a facile synthetic strategy of bead-like manganese oxide coated with carbon nanofibers (MnO-CNFs) based on electrospinning is reported, which can effectively improve the electron/ion diffusion kinetics and provide robust structural stability.

Lithium Vacancy-Tuned [CuO ] Sites for Selective CO Electroreduction to C Products.

Electrochemical CO reduction to valuable multi-carbon (C ) products is attractive but with poor selectivity and activity due to the low-efficient CC coupling. Herein, a lithium vacancy-tuned Li CuO with square-planar [CuO ] layers is developed via an electrochemical delithiation strategy. Density functional theory calculations reveal that the lithium vacancies (V ) lead to a shorter distance between adjacent [CuO ] layers and reduce the coordination number of Li around each Cu, featuring with a lower energy barrier for COCO coupling than pristine Li CuO without V .

Bismuth Oxyhydroxide-Pt Inverse Interface for Enhanced Methanol Electrooxidation Performance.

Developing efficient Pt-based electrocatalysts for the methanol oxidation reaction (MOR) is of pivotal importance for large-scale application of direct methanol fuel cells (DMFCs), but Pt suffers from severe deactivation brought by the carbonaceous intermediates such as CO. Here, we demonstrate the formation of a bismuth oxyhydroxide (BiO(OH))-Pt inverse interface via electrochemical reconstruction for enhanced methanol oxidation. By combining density functional theory calculations, X-ray absorption spectroscopy, ambient pressure X-ray photoelectron spectroscopy, and electrochemical characterizations, we reveal that the BiO(OH)-Pt inverse interface can induce the electron deficiency of neighboring Pt; this would result in weakened CO adsorption and strengthened OH adsorption, thereby facilitating the removal of the poisonous intermediates and ensuring the high activity and good stability of PtBi sample.

Elucidating the Redox Behavior in Different P-type Layered Oxides for Sodium-Ion Batteries.

Sodium layered transition-metal oxides have attracted great attention for advanced Na-ion batteries (NIBs) because of their rich structural diversity and superior specific capacity provided by not only cation redox reactions but also possible oxygen-related anionic redox reactions. However, they usually undergo severe electrochemical performance fading, especially the voltage retention during the cationic and anionic redox processes. Herein, we design and synthesize a couple of novel sodium lithium magnesium aluminum manganese oxides (NaLiMgAlMnO) with the same Na coordination environment but different oxide layer stacking sequences, namely, P2-NLMAMO and P3-NLMAMO.

Nanoheterostructures of Partially Oxidized RuNi Alloy as Bifunctional Electrocatalysts for Overall Water Splitting.

Electrocatalytic water splitting, as one of the most promising methods to store renewable energy generated by intermittent sources, such as solar and wind energy, has attracted tremendous attention in recent years. Developing efficient, robust, and green catalysts for the hydrogen and oxygen evolution reactions (HER and OER) is of great interest. This study concerns a facile and green approach for producing RuNi/RuNi oxide nanoheterostructures by controllable partial oxidation of RuNi nanoalloy, which is characterized and confirmed by various techniques, including high-resolution transmission electron microscopy and synchrotron-based X-ray absorption spectroscopy.

Elucidation of Anionic and Cationic Redox Reactions in a Prototype Sodium-Layered Oxide Cathode.

The ever-increasing demand for large-scale energy storage has driven the prosperous investigation of sodium-ion batteries (NIBs). As a promising cathode candidate for NIBs, P2-type NaNiMnO (NaNMO), a prototype sodium-layered oxide, has attracted extensive attention because of its high operating voltage and high capacity density. Although its electrochemical properties have been extensively investigated, the fundamental charge compensation mechanism, that is, the cationic and anionic redox reactions, is still elusive.

Investigating the luminescence mechanism of Mn-doped CsPb(Br/Cl) nanocrystals.

Inorganic lead halide perovskite CsPbX3 (X = Cl, Br, or I) nanocrystals are promising candidate materials for light-emitting devices and optoelectronics. Mn-Doped CsPbX3 is of particular interest, as the Mn-doping introduces an additional emission band, making this material a promising white-light emitter. In this study, Mn-doped CsPb(Br/Cl)3 nanocrystals are prepared at room-temperature and ambient pressure.

n-Alkanethiols Directly Grown on a Bare Si(111) Surface: From Disordered to Ordered Transition.

We observed the growth phase transition of n-alkanethiols (AT), CH(CH)SH, n = 4-16, directly implanted on a bare Si(111) surface, forming an AT monolayer. These monolayers were characterized with static water-contact angle, high-resolution X-ray photoelectron spectroscopy, near-edge X-ray fine-structure spectroscopy, and grazing-angle reflection absorption Fourier-transform infrared spectroscopy. The integrated spectral results indicated that the implanted n-AT molecules formed a self-oriented and densely packed monolayer through formation of an S-Si bond.

Optical Forging of Graphene into Three-Dimensional Shapes.

Atomically thin materials, such as graphene, are the ultimate building blocks for nanoscale devices. But although their synthesis and handling today are routine, all efforts thus far have been restricted to flat natural geometries, since the means to control their three-dimensional (3D) morphology has remained elusive. Here we show that, just as a blacksmith uses a hammer to forge a metal sheet into 3D shapes, a pulsed laser beam can forge a graphene sheet into controlled 3D shapes in the nanoscale.

Local oxidation and reduction of graphene.

Micrometer sized oxidation patterns were created in chemical vapor deposition grown graphene through scanning probe lithography (SPL) and then subsequently reduced by irradiation using a focused x-ray beam. Throughout the process, the films were characterized by lateral force microscopy, micro-Raman and micro-x-ray photoelectron spectroscopy. Firstly, the density of grain boundaries was found to be crucial in determining the maximum possible oxygen coverage with SPL.