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The pursuit of efficient host materials to address the sluggish redox kinetics of sulfur species has been a longstanding challenge in advancing the practical application of lithium‐sulfur batteries. In this study, amorphous carbon layer loaded with ultrafine CoP nanoparticles prepared by a one‐step in situ carbonization/phosphating method to enhance the inhibition of 2D black phosphorus (BP) on LiPSs shuttle. The carbon coating layer facilitates accelerated electron/ion transport, enabling the active involvement of BP in the conversion of soluble lithium polysulfides (LiPSs). Concurrently, the ultra‐fine CoP nanoparticles enhance the chemical anchoring ability and introduce additional catalytic sites. As a result, S@BP@C‐CoP electrodes demonstrate exemplary cycling stability (with a minimal capacity decay of 0.054 % over 500 cycles at 1 C) and superior rate performance (607.1 mAh g−1 at 5 C). Moreover, at a sulfur loading of 5.5 mg cm−2, the electrode maintains an impressive reversible areal capacity of 5.45 mAh cm−2 after 50 cycles at 0.1 C. This research establishes a promising approach, leveraging black phosphorus‐based materials, for developing high‐efficiency Li‐S batteries. [ABSTRACT FROM AUTHOR]

Ever‐increasing emissions of anthropogenic carbon dioxide (CO2) cause global environmental and climate challenges. Inspired by biological photosynthesis, developing effective strategies NeuNlto up‐cycle CO2 into high‐value organics is crucial. Electrochemical CO2 reduction reaction (CO2RR) is highly promising to convert CO2 into economically viable carbon‐based chemicals or fuels under mild process conditions. Herein, mesoporous indium supported on multi‐walled carbon nanotubes (mp‐In@MWCNTs) is synthesized via a facile wet chemical method. The mp‐In@MWCNTs electrocatalysts exhibit high CO2RR performance in reducing CO2 into formate. An outstanding activity (current density −78.5 mA cm−2), high conversion efficiency (Faradaic efficiency of formate over 90%), and persistent stability (~30 h) for selective CO2‐to‐formate conversion are observed. The outstanding CO2RR process performance is attributed to the unique structures with mesoporous surfaces and a conductive network, which promote the adsorption and desorption of reactants and intermediates while improving electron transfer. These findings provide guiding principles for synthesizing conductive metal‐based electrocatalysts for high‐performance CO2 conversion. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering spectroscopy (SERS) can provide molecular fingerprint peaks of the vibration information with great specificity and sensitivity. It is widely used in biomedical and chemical fields. Semiconductor-based substrates represent a hot spot in the field of SERS beyond conventional noble metals, and metal–organic frameworks are rarely realized for SER detection. Here, we modulate the energy-band structures of metal–organic frameworks (MOFs) further by metal oxides (MOs) to match the energy band of a target analyte. We construct MOF-encapsulated metal oxide core–shell nanoparticles (MO@MOFs) as substrates for Raman enhancement. Attributed to the high structural tailorability of both core and shell, a series of energy-band structures have been created. We perform SERS detection of rhodamine b (RhB) on MO@MOF and find that the enhanced factor of Fe3O4@MOF-(Co) and TiO2@MOF-(Ni) reach as high as 108 and 106, respectively, with low detection limits of 10–8 M, much lower than that using the corresponding MOFs. The SERS enhancement is based on mechanisms including charge transfer, interband and molecule resonances, and ground-state charge-transfer interactions. This work will promote the application of semiconductor-based nanomaterials with special modularity for surface-enhanced Raman scattering substrates. [ABSTRACT FROM AUTHOR]

We report in this letter a new type of sealed rechargeable lithium–lithium oxide battery based on reversible interconversion between superoxide (LiO2) and lithium peroxide (Li2O2). A free-standing oxygenated group-rich reduced graphene oxide aerogel (OR-rGO) with decent mechanical properties is prepared through a hydrothermal method followed by slight drying in air at room temperature and applied as a cathode in oxygen-based beyond-intercalation Li batteries. In situ Raman spectroscopy, online electrochemical mass spectroscopy, and density functional theory calculations revealed the reversible stabilization of LiO2 by the oxygenated groups on rGO during the charge process. Based on the stability of LiO2 on oxygenated group-rich reduced graphene oxide, a new sealed lithium–lithium oxide battery via reversible Li2O2/LiO2 interconversion was realized with high operating potential up to 3.65 V and no O2 evolution. Excellent cycling stability was observed for 700 cycles at a cut-off capacitance of 0.6 mA h cm−2 and a current density of 0.6 mA cm−2. [ABSTRACT FROM AUTHOR]

Direct and complete electro‐oxidation of ethanol to CO2 is highly desirable for the commercialization of the direct ethanol fuel cells but is challenging. Current electrocatalysts (mainly Pt, Pd) for ethanol oxidation reaction (EOR), unfortunately, still suffer from low CO2 selectivity and rapid performance deterioration. In this study, a new Pt/α‐PtOx/WO3 electrocatalyst containing amorphous PtOx structures is successfully synthesized via a facile hydrothermal reaction following Ar atmosphere annealing. The migration of lattice oxygens in the WO3 during the annealing process is confirmed as the mechanism for the formation and manipulation of amorphous interfaces containing PtOx species in the Pt/α‐PtOx/WO3 electrocatalyst. The obtained Pt/α‐PtOx/WO3 with tunable amorphous PtOx interfaces favors the desorption of poisoning EOR intermediates (such as CO) and high CO2 selectivity. Therefore, the state‐of‐art of the Pt/α‐PtOx/WO3 exhibits excellent EOR activity (2.76 A mg–1), stability (47.99% of the initial activity preserved after 3600 s), and particularly high CO2 selectivity (reached 21.9%, higher than most reported values for Pt or other noble metals based EOR catalysts). This study may provide a new strategy to improve the EOR performance of metal‐based catalysts and to rationally design and prepare other high‐performing electrocatalysts via engineering the amorphous interfaces. [ABSTRACT FROM AUTHOR]

Designing multi‐functional separators is one of the effective strategies for achieving high‐performance lithium–sulfur (Li–S) batteries. In this work, polyaniline (PANI) encapsulated amorphous vanadium pentoxide (V2O5) nanowires (general formula V2O5·nH2O and abbreviated as VOH) are synthesized by a facile in situ chemical oxidative polymerization method, and utilized as a basic building block for the preparation of functional interlayers on the commercial polypropylene (PP) separator, generating a VOH@PANI‐PP separator with multi‐functionalities. Compared to the crystalline V2O5, the amorphous V2O5 shows enhanced properties of polysulfide adsorption, catalytic activity, as well as ionic conductivity. Therefore, within the VOH@PANI‐PP separator, the amorphous V2O5 nanowire component contributes to the strong adsorption of polysulfides, the high catalytic activity for polysulfides conversion, and the high ionic conductivity. The PANI component further strengthens the above effects, improves the electrical conductivity, and enhances the flexibility of the modified separator. Benefiting from the synergistic effects, the VOH@PANI‐PP separator effectively suppresses polysulfide shuttling and improves the cycling stability of its composed Li–S batteries. This work provides a new research strategy for the development of efficient separators in rechargeable batteries by judiciously integrating the amorphous metal oxide with a conductive polymer. [ABSTRACT FROM AUTHOR]

Nanoconfined catalysts enhance stabilization of reaction intermediates, facilitate electron transfer, and safeguard active centers, leading to superior electrocatalytic activity, particularly in CO 2 reduction reactions (CO 2 RR). Despite their effectiveness, crafting nanoconfined catalysts is challenging due to unclear formation mechanisms. In this study, we introduce an electrochemical method to grow Pd clusters within the interlayers of two-dimensional black phosphorus, creating Pd cluster-intercalated black phosphorus (Pd-i-BP) as an electrocatalyst. Using in situ electrochemical liquid phase transmission electron microscopy (EC-TEM), we revealed the synthesis mechanism of Pd-i-BP, involving electrochemically driven Pd ion intercalation followed by reduction within the BP layers. The Pd-i-BP electrocatalyst exhibits exemplary CO 2 -to-formate conversion, achieving 90% Faradaic efficiency for formate production, owing to its distinct nanoconfined structure that stabilizes intermediates and enhances electron transfer. Density functional theory (DFT) calculations underscore the structural benefits for enhancing intermediate adsorption and catalyzing the reaction. Our insights deepen understanding of nanoconfined material synthesis, promising advanced, high-efficiency catalysts.

In sodium-ion batteries (SIBs), the low initial coulombic efficiency (ICE) is commonly induced by irreversible phase conversion and difficult desodiation, especially on transition metal compounds (TMCs). Yet the underlying physicochemical mechanism of poor reaction reversibility is still a controversial issue. Herein, by using in situ transmission electron microscopy and in situ X-ray diffraction, we demonstrate the irreversible conversion of NiCoP@C is caused by the rapid migration of P in carbon layer and preferential formation of isolated Na 3 P during discharge. By modifying the carbon coating layer, the migration of Ni/Co/P atoms is inhibited, thus the improvement of ICE and cycle stability is realized. The inhibiting of fast atom migration which induces component separation and rapid performance degradation might be applied to a wide range of electrode materials, and guides the development of advanced SIBs., (© 2023 Wiley-VCH GmbH.)

Water electrolysis offers a promising green technology to tackle the global energy and environmental crisis, but its efficiency is greatly limited by the sluggish reaction kinetics of both the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER). In this work, by growing amorphous multi-transition-metal (cobalt and iron) oxide on two-dimensional (2D) black phosphorus (BP), we develop a bifunctional electrocatalyst (CoFeO@BP), which is able to efficiently catalyze both HER and OER. The overpotentials for the hybrid CoFeO@BP catalyst to reach a current density of 10 mA cm -2 in 1 m KOH are 88 and 266 mV for HER and OER, respectively. Based on a series of ex-situ and in situ investigations, the excellent catalytic performance of CoFeO@BP is found to result from the adaptive surface structure under reduction and oxidation potentials. CoFeO@BP can be transformed to CoFe phosphide under reduction potential, in situ generating the real active catalyst for HER., (© 2020 Wiley-VCH GmbH.)

The colorimetric biosensors have attracted intensive interest; however, their relatively low sensitivity limits their applications in clinic detection. Herein, we develop an effective colorimetric biosensor based on highly catalytic active Au nanoparticle-decorated Bi 2 Se 3 (Au/Bi 2 Se 3 ) nanosheets. Au/Bi 2 Se 3 nanosheets are facilely synthesized by simply sonicating Au precursor with the as-synthesized Bi 2 Se 3 nanosheets in aqueous solution. Because of the low redox potential and typical topological insulating properties, Bi 2 Se 3 nanosheets is capable of providing and accumulating electrons on its surface. Such unique properties of Bi 2 Se 3 nanosheets contribute to strong synergistic catalytic effects with Au nanoparticles, particularly when Au/Bi 2 Se 3 nanosheets are utilized for catalyzing the reduction of 4-nitrophenol (4-NP) by NaBH 4 (K = 386.67 s -1 g -1 ). The excellent catalytic activity of Au/Bi 2 Se 3 nanosheets can be "switched off" upon treatment of antibody of cancer biomarker such as anticarcinoembryonic antibody (anti-CEA). Addition of the corresponding antigen such as cancer biomarker carcinoembryonic antibody (CEA) can successively help "switch on" the catalytic activity of Au/Bi 2 Se 3 nanosheets, where the resuming degree however depends on the antigen concentration. This cancer biomarker depended catalytic behavior therefore allows Au/Bi 2 Se 3 nanosheets to be employed as a colorimetric sensor for detection of a particular cancer biomarker, for the reduction of 4-nitrophenol (4-NP) by NaBH 4 itself involves apparent color change. The sensor shows high sensitivity and selectivity for the cancer biomarker, even for a concentration as low as 160 pg/mL for CEA, which fully satisfies the requirement for real clinical applications. The developed colorimetric sensor shows good generality for detection of different types of cancer biomarkers, such as α-fetoprotein (AFP) and prostate-specific antigen (PSA). Furthermore, real clinic sample analyzing result shows that the prepared biosensor is efficient for detection of CEA, providing an alternative method in cancer diagnosis.