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The low-cost room-temperature sodium-sulfur battery system is arousing extensive interest owing to its promise for large-scale applications. Although significant efforts have been made, resolving low sulfur reaction activity and severe polysulfide dissolution remains challenging. Here, a sulfur host comprised of atomic cobalt-decorated hollow carbon nanospheres is synthesized to enhance sulfur reactivity and to electrocatalytically reduce polysulfide into the final product, sodium sulfide. The constructed sulfur cathode delivers an initial reversible capacity of 1081 mA h g −1 with 64.7% sulfur utilization rate; significantly, the cell retained a high reversible capacity of 508 mA h g −1 at 100 mA g −1 after 600 cycles. An excellent rate capability is achieved with an average capacity of 220.3 mA h g −1 at the high current density of 5 A g −1 . Moreover, the electrocatalytic effects of atomic cobalt are clearly evidenced by operando Raman spectroscopy, synchrotron X-ray diffraction, and density functional theory. Room-temperature sodium-sulfur batteries hold promise, but are hindered by low reversible capacity and fast capacity fade. Here the authors construct a multifunctional sulfur host comprised of cobalt-decorated carbon nanospheres that impart attractive performance as a cathode in a sodium sulfide battery.

The precise control of the morphology of inorganic materials during their synthesis is important yet challenging. Here we report that the morphology of a wide range of inorganic materials, grown by rapid precipitation from a metal cation solution, can be tuned during their crystallization from one- to three-dimensional (1D to 3D) structures without the need for capping agents or templates. This control is achieved by adjusting the balance between the electrolytic dissociation ( α ) of the reactants and the supersaturation ( S ) of the solutions. Low- α, weak electrolytes promoted the growth of anisotropic (1D and 2D) samples, with 1D materials favoured in particular at low S . In contrast, isotropic 3D polyhedral structures could only be prepared in the presence of strong electrolyte reactants ( α  ≈ 1) with low S . Using this strategy, a wide range of materials were prepared, including metal oxides, hydroxides, carbonates, molybdates, oxalates, phosphates, fluorides and iodate with a variety of morphologies. Precipitation enables the straightforward production of a variety of inorganic materials, but the rapid reaction rates involved typically make controlling their morphologies difficult. Now, the growth of either one-, two- or three-dimensional materials has been promoted by tuning of the reactants’ electrolytic dissociation and solution supersaturation, without the need for capping agents and templates.

The effective flow of electrons through bulk electrodes is crucial for achieving high-performance batteries, although the poor conductivity of homocyclic sulfur molecules results in high barriers against the passage of electrons through electrode structures. This phenomenon causes incomplete reactions and the formation of metastable products. To enhance the performance of the electrode, it is important to place substitutable electrification units to accelerate the cleavage of sulfur molecules and increase the selectivity of stable products during charging and discharging. Herein, we develop a single-atom-charging strategy to address the electron transport issues in bulk sulfur electrodes. The establishment of the synergistic interaction between the adsorption model and electronic transfer helps us achieve a high level of selectivity towards the desirable short-chain sodium polysulfides during the practical battery test. These finding indicates that the atomic manganese sites have an enhanced ability to capture and donate electrons. Additionally, the charge transfer process facilitates the rearrangement of sodium ions, thereby accelerating the kinetics of the sodium ions through the electrostatic force. These combined effects improve pathway selectivity and conversion to stable products during the redox process, leading to superior electrochemical performance for room temperature sodium-sulfur batteries. Efficient charge transfer in sulfur electrodes is a crucial challenge for sodium-sulfur batteries. Here, the authors developed a machine-learning-assisted approach to quickly identify effective single-atom catalysts that enhance selectivity for short-chain sodium polysulfides, leading to improved battery performance.

HighlightsA ‘solid–liquid’ conversion for increasing the sulfur content from ~ 50 to 72% for RT Na–S batteries is developed.The redox mechanisms of two types of sulfur: sulfur on the surface of a cathode host (155S) and sulfur in the pores of the host (300S) in ether and carbonate ester electrolytes are studied.The function of NaNO3 additive on modifying Na anode and confining the shuttle effect of dissolving polysulfides during ‘solid–liquid’ conversion is visualized.This work reports influence of two different electrolytes, carbonate ester and ether electrolytes, on the sulfur redox reactions in room-temperature Na–S batteries. Two sulfur cathodes with different S loading ratio and status are investigated. A sulfur-rich composite with most sulfur dispersed on the surface of a carbon host can realize a high loading ratio (72% S). In contrast, a confined sulfur sample can encapsulate S into the pores of the carbon host with a low loading ratio (44% S). In carbonate ester electrolyte, only the sulfur trapped in porous structures is active via ‘solid–solid’ behavior during cycling. The S cathode with high surface sulfur shows poor reversible capacity because of the severe side reactions between the surface polysulfides and the carbonate ester solvents. To improve the capacity of the sulfur-rich cathode, ether electrolyte with NaNO3 additive is explored to realize a ‘solid–liquid’ sulfur redox process and confine the shuttle effect of the dissolved polysulfides. As a result, the sulfur-rich cathode achieved high reversible capacity (483 mAh g−1), corresponding to a specific energy of 362 Wh kg−1 after 200 cycles, shedding light on the use of ether electrolyte for high-loading sulfur cathode.

Developing low‐cost and high‐voltage manganese (Mn)‐based Na superionic conductor (NASICON) cathode materials have attracted extensive interest. The low capacity and cycling instability of Na4MnAl(PO4)3 (NMAP), however, limits its performance in sodium‐ion batteries (SIBs). Herein, a binary Na4Mn0.5Fe0.5Al(PO4)3 (MNFAP) is fabricated to ease the structural instability and, in turn, deliver an improved reversible capacity of 102 mAh g−1 at 0.1 C and a high energy density of 287.7 Wh kg−1. The synergistic interaction of Fe and Mn in Na4Mn0.5Fe0.5Al(PO4)3/C composite leads to a one‐phase solid‐solution reaction mechanism with high structural reversibility. Theoretical calculations have also been performed to explain the upshifted voltage platform of both Fe2+/Fe3+ and Mn3+/Mn4+ redox potentials. The rational design of NASICON‐type cathodes by regulating their composition with dual metal ions provides new perspectives for developing high‐performance SIBs. A comprehensive investigation of the structural and electrochemical properties of a binary Na superionic conductor‐structured material of Na4Mn0.5Fe0.5Al(PO4)3, and synergistic effects of Mn and Fe significantly enhance the energy density of Mn‐based polyanionic compounds.

HighlightsThe LiNO3-implanted electroactive β phase polyvinylidene fluoride-co-hexafluoropropylene was built as an artificial solid electrolyte interphase layer for dendrite suppression.The electronegatively charged polymer layer can capture Li ion on its surface to form Li-ion charged channels and recompense the ionic flux of electrolytes via continuous supply of Li ion.The modified Li anode achieved a long cycle life over 2000 h under ultrahigh Li utilization of 50% in symmetric cell and worked in full cell for 100 cycles at harsh condition of extremely low N/P of 0.83.The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite growth. Resolving this issue will be key to achieving high-performance lithium metal batteries (LMBs). Herein, we construct a lithium nitrate (LiNO3)-implanted electroactive β phase polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) crystalline polymorph layer (PHL). The electronegatively charged polymer chains attain lithium ions on the surface to form lithium-ion charged channels. These channels act as reservoirs to sustainably release Li ions to recompense the ionic flux of electrolytes, decreasing the growth of lithium dendrites. The stretched molecular channels can also accelerate the transport of Li ions. The combined effects enable a high Coulombic efficiency of 97.0% for 250 cycles in lithium (Li)||copper (Cu) cell and a stable symmetric plating/stripping behavior over 2000 h at 3 mA cm−2 with ultrahigh Li utilization of 50%. Furthermore, the full cell coupled with PHL-Cu@Li anode and LiFePO4 cathode exhibits long-term cycle stability with high-capacity retention of 95.9% after 900 cycles. Impressively, the full cell paired with LiNi0.87Co0.1Mn0.03O2 maintains a discharge capacity of 170.0 mAh g−1 with a capacity retention of 84.3% after 100 cycles even under harsh condition of ultralow N/P ratio of 0.83. This facile strategy will widen the potential application of LiNO3 in ester-based electrolyte for practical high-voltage LMBs.

Rechargeable batteries have been indispensable for various portable devices, electric vehicles, and energy storage stations. The operation of rechargeable batteries at low temperatures has been challenging due to increasing electrolyte viscosity and rising electrode resistance, which lead to sluggish ion transfer and large voltage hysteresis. Advanced electrolyte design and feasible electrode engineering to achieve desirable performance at low temperatures are crucial for the practical application of rechargeable batteries. Herein, the failure mechanism of the batteries at low temperature is discussed in detail from atomic perspectives, and deep insights on the solvent–solvent, solvent–ion, and ion–ion interactions in the electrolytes at low temperatures are provided. The evolution of electrode interfaces is discussed in detail. The electrochemical reactions of the electrodes at low temperatures are elucidated, and the approaches to accelerate the internal ion diffusion kinetics of the electrodes are highlighted. This review aims to deepen the understanding of the working mechanism of low‐temperature batteries at the atomic scale to shed light on the future development of low‐temperature rechargeable batteries. Low‐temperature performance of rechargeable batteries is crucial for their practical applications. This review comprehensively reveals the challenges and solutions for low‐temperature aqueous and non‐aqueous rechargeable batteries from an atomic perspective, deep insights on the solvent–solvent, solvent–ion, and ion–ion interactions in the electrolytes are provided, recent advances in the rational design of electrolytes, interfaces, and electrodes are included.

Conversion of carbon dioxide (CO2) to valuable chemicals and feedstocks through electrochemical reduction holds promise for achieving carbon neutrality and mitigating global warming. C2+ products are of interest due to their higher economic value. Since the CO2 to C2+ conversion process involves multiple steps, tandem catalytic strategies are commonly employed in the design of electrochemical CO2 reduction reaction (CO2RR) catalysts and systems/reactors. Among the diverse catalysts that are capable of reducing CO2 to CO, Cu stands out for more efficiently further converting CO to C2+ products. In this review, the emerging Cu‐based tandem catalysts and their impact on CO2RR performance, focusing on three positional relationships are summarized. It delves into the integration of tandem catalytic strategies into membrane electrolyzers, utilizing catalyst‐coated substrate (CCS) and catalyst‐coated membrane (CCM) technologies. Several typical examples are presented to illustrate this integration. Finally, the challenges and prospects of applying tandem strategies in the development of CO2RR catalysts/systems, as well as their device‐level implementation are indicated. This review discusses the emerging Cu‐based tandem catalytic systems, ranging from catalyst design to the integration of tandem catalysts into the membrane electrode assembly assisted by catalyst‐coated substrate and catalyst‐coated membrane technologies, in the field of electrochemical reduction of CO2 to multiple‐carbon products. It covers recent advances, challenges, and practical perspectives.

IntroductionOral health research provides evidence for policy and practice, yet no study has comprehensively mapped the scope of oral health research in Malaysia. The COVID-19 pandemic has also created a great impact on oral healthcare in Malaysia, including the dental care delivery. Additionally, there is a notable lack of research focusing on oral health during and after the COVID-19 pandemic. Therefore, this scoping review will aim to map the landscape of oral health research conducted in Malaysia and identify key topics, study designs, populations studied and gaps in the literature, in order to inform future research priorities and policy, particularly in the post-COVID-19 era.Methods and analysisThe methodology draws on Arksey and O’Malleys’ seminal framework for the scoping review and will be reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Review (PRISMA-ScR) guidelines. We will search five major electronic databases—PubMed, Scopus, ProQuest, Cochrane and Web of Science—as well as selected grey literature sources (eg, theses, dissertations and conference proceedings) for studies published in English from January 2014 to December 2024. Studies of any design related to oral health in Malaysia will be included. Two reviewers will be performing title and abstract screening, in which they will be working independently. The included publication will undergo a full-text review, and references cited in these studies will be examined following the inclusion criteria. The PRISMA-ScR flow diagram will be used as a guide throughout the process. Data will be extracted, analysed and charted according to key categories identified in the included publications. A narrative synthesis and descriptive statistics will be presented.Ethics and disseminationThe results of this scoping review will illustrate an overview and provide a better understanding regarding the oral health research in the Malaysian context; whether research has already been conducted, is currently ongoing and is still needed; and which areas should be prioritised for future investigation. As this review will use publicly available literature, formal ethics approval will not be required. The findings will be submitted for publication in an open-access peer-reviewed journal, presented at national and regional conferences and shared with Malaysian dental professional bodies and relevant stakeholders.Trial registration numberThe protocol of this scoping review is registered with the Open Science Framework and is available at osf.io/hjq6m.

Rechargeable lithium/sodium–sulfur batteries working at room temperature (RT‐Li/S, RT‐Na/S) appear to be a promising energy storage system in terms of high theoretical energy density, low cost, and abundant resources in nature. They are, thus, considered as highly attractive candidates for future application in energy storage devices. Nevertheless, the solubility of sulfur species, sluggish kinetics of lithium/sodium sulfide compounds, and high reactivity of metallic anodes render these cells unstable. As a consequence, metal–sulfur batteries present low reversible capacity and quick capacity loss, which hinder their practical application. Investigations to address these issues regarding S cathodes are critical to the increase of their performance and our fundamental understanding of RT‐Li/S and RT‐Na/S battery systems. Metal–sulfur interactions, recently, have attracted considerable attention, and there have been new insights on pathways to high‐performance RT‐Li/Na sulfur batteries, due to the following factors: (1) deliberate construction of metal–sulfur interactions can enable a leap in capacity; (2) metal–sulfur interactions can confine S species, as well as sodium sulfide compounds, to stop shuttle effects; (3) traces of metal species can help to encapsulate a high loading mass of sulfur with high‐cost efficiency; and (4) metal components make electrodes more conductive. In this review, we highlight the latest progress in sulfide immobilization via constructing metal bonding between various metals and S cathodes. Also, we summarize the storage mechanisms of Li/Na as well as the metal–sulfur interaction mechanisms. Furthermore, the current challenges and future remedies in terms of intact confinement and optimization of the electrochemical performance of RT‐Li/Na sulfur systems are discussed in this review. This review summarizes the latest progress in the sulfide immobilization, storage mechanisms of Li/Na as well as the metal–sulfur interaction mechanisms. Furthermore, the current challenges and future remedies in terms of intact confinement and optimization of the electrochemical performance of room temperature‐Li/Na sulfur systems are also discussed.