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Tin-based sulfides, such as SnS2, have garnered attention as lithium-ion anode materials due to their layer structure and high conductivity capacity. However, during the lithium alloying/dealloying cycles, SnS2 material exhibits a rapid capacity decay due to the volume expansion, which hinders the application of SnS2. In this study, a heterostructure composite material anchored on exfoliated graphite, designated as nano SnS2S3/Sn3S4/FeS/Fe7S8 anchored on 15.0 wt% exfoliated graphite (FSS/G-15%), was synthesized by heating a mixture of inexpensive reducing agent Fe powder and SnS2 powder, followed by ball milling with 15.0 wt% commercial graphite. Experimental results demonstrated that FSS/G-15% had exhibited optimal overall Li+ storage performance, achieving approximately 1306.7, 1199.2, 1033.1, 882.3, 707.3, 507, 366.3, 255.6, and 203.5 mA hg−1 at current densities of 0.1, 0.2, 0.5, 1, 2, 4, 6, 8, and 10 Ag−1, respectively, surpassing the majority of SnS2-based anode materials. The simplicity and efficiency of the synthetic method may have potential implications in various fields in the future. [ABSTRACT FROM AUTHOR]

The burden of premature atherosclerotic cardiovascular disease (ASCVD) has increased rapidly in China. Using the China Health and Nutrition Survey (CHNS) data, we assessed the risk factors of premature ASCVD (age of diagnosis: <55 years for men and <65 years for women). Propensity score matching was used to reduce selection bias. Multivariable Cox proportional-hazards analyses indicated that factors associated with increased risk of premature ASCVD included hypertension (adjusted hazard ratio [HRadj.] = 1.68), obesity (HRadj. = 1.64), and high carbohydrate intake (HRadj. = 1.46). Conversely, participants with medical insurance (HRadj. = 0.42), high urbanization index (HRadj. = 0.53), and high household income (HRadj. = 0.48) had lower risk of premature ASCVD. When comparing premature vs non-premature ASCVD participants, those who were obese (HRadj. = 2.08) or living in more urbanized areas had higher hazards of early onset (HRadj. = 2.29). [ABSTRACT FROM AUTHOR]

The development of efficient, non-toxic, and cost-effective white-light emitters is crucial for advancing lighting technology. Here, we present a groundbreaking study on a new all-inorganic perovskite crystal, CsCaCl3:Mn2+, which exhibits temperature sensing and hue-tunable white light emission. The CsCaCl3 matrix emits broad blue light at 455 nm due to self-trapped exciton (STE) emission. Upon Mn2+ doping, the CsCaCl3:Mn2+ crystal emits broad yellow light at 555 nm, originating from the Mn2+ 4T1(G)–6A1(S) transition. Increasing Mn2+ concentration led to a decrease in blue emission intensity, accompanied by enhanced yellow emission, suggesting an energy transfer from STEs to Mn2+. The enhanced stability of CsCaCl3:Mn2+ compared to pure CsCaCl3 is demonstrated through thermal analysis. The distinctive temperature-dependent responses of STE and Mn2+ emissions in CsCaCl3:Mn2+ suggest its potential application in temperature sensing. The synthesis process for this luminescent crystal is both straightforward and scalable, making it a promising candidate for large-scale applications. [ABSTRACT FROM AUTHOR]

As a new type of negative electrode material for SIBs, (iron germanium sulfide) Fe2GeS4 is considered a highly promising negative electrode material for SIBs owing to its high theoretical capacity, fast Na+ diffusion kinetics, and good thermal stability. In practical applications, it is crucial to synthesize the high-capacity/reversible nanostructured Fe2GeS4-based negative electrodes through an easily executable method. In this study, a two-step synthesis method to prepare nanostructured Fe2GeS4 anchored on graphite (Fe2GeS4/G-15%) was employed: the commercial FeS, S, and Ge powders were mixed and heated, and then graphite was added for ball milling. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that there is a strong interaction between the nanostructured Fe2GeS4 powder and the exfoliated graphite, forming a highly stable nanocomposite material, which is beneficial for improving the reversible charge-discharge performance of the material. When used as a negative electrode material for SIBs, the prepared Fe2GeS4/G-15% exhibited a capacity of 665.5 mAh g−1 during the second cycle at 0.1 A g−1 and could maintain a capacity of 519 mAh g−1 even after the 60th cycle. Considering the simple synthesis process employed in this study, it provides a reference for the production of high-performance Fe2GeS4-based negative electrode materials for SIBs. [ABSTRACT FROM AUTHOR]

Sn-based alloys have emerged as high-capacity, low-working voltage anodes for sodium-ion batteries (SIBs) in recent years, but the complex synthesis processes for highly reversible anodes have impeded their practical application. Herein, DFT calculations demonstrated that SnS2 and Fe can undergo a series of reactions to form Fe–Sn alloys, along with high conductivity/reversible FeSx sulfides. Guided by theoretical calculations, FeS/SnS, FeSn2/FeS/SnS, and FeSn/FeSn2/FeS/SnS heterostructure composites anchored on exfoliated graphite (namely FSS-1/G-15%, FSS-2/G-15%, and FSS-3/G-15%, respectively) were fabricated by annealing Fe and SnS2 mixed powders, and subsequently, ball milling with 15 wt% graphite. Cyclic voltammetry tests, DFT calculations, and ex situ XRD analysis co-confirmed that FeSn and FeSn2 are partially reversible, while FeS and SnS are reversible. FSS-3/G-15% exhibits the best overall Na+-storage performances, which delivered approximately 402, 351, 326, 302, 270, and 259 mA h g−1 at 0.1, 1, 2, 4, 8, and 10 A g−1, with an initial coulombic efficiency of 83.3% at 0.1 A g−1, surpassing most of the recent-reported analogous alloy anodes. The universal material synthesis method only needs one step of thermal reaction, and then ball milling, which may hold great promise in future applications in various fields. [ABSTRACT FROM AUTHOR]

Nickel, cobalt, and manganese oxides are easily obtainable non-noble metal catalysts for water splitting. However, the relationship between composition and catalysts' performance still needs systematic studies. Herein, guided by theoretical calculations, a low overpotential, easily prepared Mn-doped Co3O4 was deposited on graphite plates for water splitting. The 30% Mn-doped Co3O4 (Co2.1Mn0.9O4) required the lowest overpotential for oxygen evolution reaction (OER), in which the Co2.1Mn0.9O4 reached 20, 30, and 50 mA cm−2 in the overpotentials of 425, 451, and 487 mV, respectively, with 90% IR compensation. Under overall water-splitting conditions, the current density reached 30 mA cm−2 at an overpotential of 0.78 V without IR compensation. Charge density difference analysis illustrates that doped Mn provides electrons for O atoms, and that Mn doping also promotes the electron fluctuation of Co atoms. XPS analysis reveals that Mn-doping increases the chemical valence of the Co atom, and that the doped Mn atom also exhibits higher chemical valence than the Mn of Mn3O4, which is advantageous to boost the form of based-OOH* radical, then decrease the overpotential. Considering the particular simplicity of growing the Co2.1Mn0.9O4 on graphite plates, this work is expected to provide a feasible way to develop the high-performance Co-Mn bimetallic oxide for water splitting. [ABSTRACT FROM AUTHOR]

As a unique nanofabrication technology, atomic layer deposition (ALD) has been used in the microelectronics, catalysis, environmental and energy fields. As an energy and catalytic material, nickel sulfide has excellent electrochemical and catalytic activities and has attracted extensive attention. In this work, the reaction mechanism for nickel sulfide ALD from an amidine metal precursor was investigated using density functional theory (DFT) calculations. The results show that the first amidine ligand of bis(N,N′-di-tert-butylacetamidinato)nickel(II) [Ni(tBu-MeAMD)2] can be easily eliminated on the sulfhydrylated surface. The second amidine ligand can also react with the adjacent sulfhydryl group to generate the N,N′-di-tert-butylacetamidine (tBu-MeAMD-H) molecule, which can strongly interact with the Ni atom on the surface and be difficult to be desorbed. In the subsequent H2S reaction, the tBu-MeAMD-H molecule can be exchanged with the H2S precursor. Ultimately, the tBu-MeAMD-H molecule can be desorbed and H2S can be dissociated to form two sulfhydrylated groups on the surface. Meanwhile, the –SH of a H2S molecule can be exchanged with the second tBu-MeAMD ligand. These insights into the reaction mechanism of nickel sulfide ALD can provide theoretical guidance to design the metal amidinate precursors and improve the ALD process for metal sulfides. [ABSTRACT FROM AUTHOR]

Nano-polycrystalline Sn2S3/Sn3S4/FeS/Fe7S8 sulfides anchored on graphene were synthesized via annealing SnS2 and Fe followed by homogeneously combining them with exfoliated graphite. When applied as an anode for a sodium-ion battery, the reversible capacity reached 863 mA h g−1 at 100 mA g−1. This facial materials synthesis method may be applied in various fields. [ABSTRACT FROM AUTHOR]

Porous metal foams (e.g., Ni/Cu/Ti) are applied as catalyst supports extensively for water splitting due to their large specific area and excellent conductivity, however, intrinsic bubble congestion is unavoidable because of the irregular three‐dimensional (3D) networks, resulting in high polarization and degraded electrocatalytic performances. To boost the H2O decomposition kinetics, the immediate bubble removal and water supply sequential in the gas–liquid–solid interface is essential. Inspired by the high efficiency of water/nutrient transport in the capillaries plants, this work designs a graphene‐based capillary array with side holes as catalyst support to manage the bubble release and water supply via a Z‐axis controllable digital light processing (DLP) 3D printing technology. Like planting rice, a low‐cost, high‐active CoNi carbonate hydroxide (CoNiCH) is planted on support. A homemade cell can reach 10 mA cm−2 in 1.51 V, and be kept at 30 mA cm−2 for 60 h without noticeable degradation, surpassing most of the known cells. This research provides a promising avenue to design and prepare advanced catalysts in various fields, including energy applications, pollutant treatment, and chemical synthesis. [ABSTRACT FROM AUTHOR]

As an important inorganic material, zirconium dioxide (ZrO2) has a wide range of applications in the fields of microelectronics, coating, catalysis and energy. Due to its high dielectric constant and thermodynamic stability, ZrO2 can be used as dielectric material to replace traditional silicon dioxide. Currently, ZrO2 dielectric films can be prepared by atomic layer deposition (ALD) using water and zirconium precursors, namely H2O-based ALD. Through density functional theory (DFT) calculations and first-principles molecular dynamics (FPMD) simulations, the adsorption and dissociation of water molecule on the ZrO2 surface and the water–solid interface reaction were investigated. The results showed that the ZrO2 (111) surface has four Lewis acid active sites with different coordination environments for the adsorption and dissociation of water. The Zr atom on the surface can interacted with the O atom of the water molecule via the p orbital of the O atom and the d orbital of the Zr atom. The water molecules could be dissociated via the water–solid interface reaction of the first or second layer of water molecules with the ZrO2 (111) surface. These insights into the adsorption and dissociation of water and the water–solid interface reaction on the ZrO2 surface could also provide a reference for the water–solid interface behavior of metal oxides, such as H2O-based ALD. [ABSTRACT FROM AUTHOR]