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The Zn‐air battery (ZAB) is attracting increasing attention due to its high safety and preeminent performance. However, the practical application of ZAB relies heavily on developing durable support materials to replace conventional carbon supports which have unrecoverable corrosion issues, severely jeopardizing ZAB performance. Herein, a novel porous FeCo glassy alloy is developed as a bifunctional catalytic support for ZAB. The conducting skeleton of the porous glassy alloy is used to stabilize oxygen reduction cocatalysts, and more importantly, the FeCo serves as the primary phase for oxygen evolution. To demonstrate the concept of catalytic glassy alloy support, ultrasmall Pd nanoparticles are anchored, as oxygen reduction active sites, on the porous FeCo (noted as Pd/FeCo) for ZAB. The Pd/FeCo exhibits a significantly improved electrocatalytic activity for oxygen reduction (a half‐wave potential of 0.85 V) and oxygen evolution (a potential of 1.55 V to reach 10 mA cm−2) in the alkaline media. When used in the ZAB, the Pd/FeCo delivers an output power density of 117 mW cm−2 and outstanding cycling stability for over 200 h (400 cycles), surpassing the conventional carbon‐supported Pt/C+IrO2 catalysts. Such an integrated design that combines highly active components with a porous architecture provides a new strategy to develop novel nanostructured electrocatalysts. [ABSTRACT FROM AUTHOR]

A crucial step toward clean hydrogen (H2) energy production through water electrolysis is to develop high‐stability catalysts, which can be reliably used at high current densities for a long time. So far, platinum group metals (PGM) and their oxides, for example, Pt and iridium oxide (IrO2) have been well‐regarded as the criterion for hydrogen and oxygen evolution reactions (HER and OER) electrocatalysts. However, the PGM catalysts usually undergo severe performance decay during the long‐term operation. Herein, the in situ growth of iron phosphosulfate (Fe2P2S6) nanocrystals (NCs) catalysts on carbon paper synthesized by combing chemical vapor deposition with solvent‐thermal treatment is reported to show competitive performance and stability as compared to the state‐of‐the‐art PGM catalysts in a real water electrolyzer. A current density of 370 mA cm−2 is achieved at 1.8 V when using Fe2P2S6 NCs as bifunctional catalysts in an anion exchange membrane water electrolyzer. The Fe2P2S6 NCs also show much better stability than the Pt‐IrO2 catalysts at 300 mA cm−2 for a continuous 24 h test. The surface generated FeOOH on Fe2P2S6 is the real active site for OER. These results indicate that the Fe2P2S6 NCs potentially can be used to replace PGM catalysts for practical water electrolyzers. [ABSTRACT FROM AUTHOR]

Presents a study that examined the high population inversion of magnesium ions in a laser-irradiated microtube. Methodology; Analysis of the mechanism for inversion; Examination of the densitometric traces of the spectrum of magnesium ions.

Here, we demonstrate that a type-II g-C3N4 nanosheet (CNNS)/W18O49 heterostructure composite can be switched to Z-scheme through the deposition of Au nanoparticles (NPs) on the surface of CNNS. As a direct result, the designed Au/CNNS/W18O49 heterostructure shows enhanced photocatalytic performance for Cr(vi) reduction than the CNNS/W18O49 heterostructure and single components (CNNS and W18O49) under visible light irradiation. [ABSTRACT FROM AUTHOR]

A visible-light-responsive bismuth-based metal-organic framework (Bi-mna) is demonstrated to show good photoelectric and photocatalytic properties. Combining experimental and theoretical results, a ligand-to-ligand charge transfer (LLCT) process is found to be responsible for the high performance, which gives rise to a longer lifetime of photogenerated charge carriers. Our results suggest that bismuth-based MOFs could be promising candidates for the development of efficient visible-light photocatalysts. [ABSTRACT FROM AUTHOR]

CoS2 nanoparticles co‐doped with N and P are embedded in the periodic TiO2 nanocavities, which serve as bi‐functional electrocatalysts for oxygen reduction and evolution reactions. As described by Ke Bi, Xiaohui Wang, Yang Yang, and co‐workers in article number 1804540, the increased number of active sites results from N‐dopants and outstanding stability are achieved for superior electrocatalytic performance of Zn‐Air batteries. [ABSTRACT FROM AUTHOR]

Solid-state electrolytes (SSEs) play a vital role in the development of high-energy all-solid-state batteries. However, most adopted mechanical ball milling and/or high-temperature annealing are ineffective approaches for large-scale synthesis. Herein, a universal and scalable hydrate-assisted strategy for the synthesis of oxychloride SSEs is developed based on the chemical reaction among alkali chlorides, AlCl 3 , and AlCl 3 ·6H 2 O. The synthesized aluminum-based oxychloride SSEs possess a high Li + conductivity over 1 mS cm -1 at 30 °C. The final aluminum-based oxychloride SSEs are structurally heterogeneous with nm-sized LiCl-like and LiAlCl 4 crystallites and large amounts of amorphous [Al a O b Cl c ] (2 b + c -3 a )- components. Faster local mobility of Li + ions in amorphous structures is verified and is attributable to weakened Li + -X - interactions ensured by the [Al a O b Cl c ] (2 b + c -3 a )- polyanions. The potential applications for this synthesis technique are further demonstrated by kilogram-scale reactions and synthesis of other oxychloride SSEs including zirconium-based and tantalum-based analogs. These findings not only provide a new simple, scalable, and energy-efficient synthesis route for oxychloride SSEs but also further promote their application in all-solid-state batteries., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

The formation and preservation of the active phase of the catalysts at the triple-phase interface during CO 2 capture and reduction is essential for improving the conversion efficiency of CO 2 electroreduction toward value-added chemicals and fuels under operational conditions. Designing such ideal catalysts that can mitigate parasitic hydrogen generation and prevent active phase degradation during the CO 2 reduction reaction (CO 2 RR), however, remains a significant challenge. Herein, we developed an interfacial engineering strategy to build a new SnO x catalyst by invoking multiscale approaches. This catalyst features a hierarchically nanoporous structure coated with an organic F-monolayer that modifies the triple-phase interface in aqueous electrolytes, substantially reducing competing hydrogen generation (less than 5%) and enhancing CO 2 RR selectivity (∼90%). This rationally designed triple-phase interface overcomes the issue of limited CO 2 solubility in aqueous electrolytes via proactive CO 2 capture and reduction. Concurrently, we utilized pulsed square-wave potentials to dynamically recover the active phase for the CO 2 RR to regulate the production of C1 products such as formate and carbon monoxide (CO). This protocol ensures profoundly enhanced CO 2 RR selectivity (∼90%) compared with constant potential (∼70%) applied at -0.8 V (V vs RHE). We further achieved a mechanistic understanding of the CO 2 capture and reduction processes under pulsed square-wave potentials via in situ Raman spectroscopy, thereby observing the potential-dependent intensity of Raman vibrational modes of the active phase and CO 2 RR intermediates. This work will inspire material design strategies by leveraging triple-phase interface engineering for emerging electrochemical processes, as technology moves toward electrification and decarbonization.

Fine-tuning the exposed active sites of platinum group metal (PGM)-based materials is an efficient way to improve their electrocatalytic performance toward large-scale applications in renewable energy devices such as Zn-air batteries (ZABs). However, traditional synthetic methods trade off durability for the high activity of PGM-based catalysts. Herein, a novel dynamic CO 2 -bubble template (DCBT) approach was established to electrochemically fine-tuning the exposed Pt active sites in PtFeNi (PFN) porous films (PFs). Particularly, CO 2 bubbles were intentionally generated as gas-phase templates by methanol electrooxidation. The generation, adsorption, residing, and desorption of CO 2 bubbles on the surface of PFN alloys were explored and controlled by adjusting the frequency of applied triangular-wave voltage. Thereby, the surface morphology and Pt exposure of PFN PFs were controllably regulated by tuning the surface coverage of CO 2 bubbles. Consequently, the Pt 1.1% Fe 8.8% Ni PF with homogeneous nanoporous structure and sufficiently exposed Pt active sites was obtained, showing preeminent activities with a half-wave potential ( E 1/2 ) of 0.87 V and onset overpotential (η onset ) of 288 mV at 10 mA cm -2 for oxygen reduction and evolution reactions (ORR and OER), respectively, at an ultralow Pt loading of 0.01 mg cm -2 . When tested in ZABs, a high power density of 175.0 mW cm -2 and a narrow voltage gap of 0.64 V were achieved for the long cycling tests over 500 h (750 cycles), indicating that the proposed approach can efficiently improve the activity of PGM catalysts by fine-tuning the microstructure without compromising the durability.

To produce efficient ORR catalysts with low Pt content, PtNi porous films (PFs) with sufficiently exposed Pt active sites were designed by an approach combining electrochemical bottom-up (electrodeposition) and top-down (anodization) processes. The dynamic oxygen-bubble template (DOBT) programmably controlled by a square-wave potential was used to tune the catalyst morphology and expose Pt active facets in PtNi PFs. Surface-bounded species, such as hydroxyl (OH * , *=surface site) on the exposed PtNi PFs surfaces were adjusted by the applied anodic voltage, further affecting the dynamic oxygen (O 2 ) bubbles adsorption on Pt. As a result, PtNi PF with enriched Pt(111) facets (denoted as Pt 3.5 % Ni PF) was obtained, showing prominent ORR activity with an onset potential of 0.92 V (vs. RHE) at an ultra-low Pt loading (0.015 mg cm -2 )., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Here, we demonstrate that a type-II g-C3N4 nanosheet (CNNS)/W18O49 heterostructure composite can be switched to Z-scheme through the deposition of Au nanoparticles (NPs) on the surface of CNNS. As a direct result, the designed Au/CNNS/W18O49 heterostructure shows enhanced photocatalytic performance for Cr(vi) reduction than the CNNS/W18O49 heterostructure and single components (CNNS and W18O49) under visible light irradiation.