We show that intercalation of cations (Na+, Ca2+, Ni2+, and Co2+) into the interlayer region 1T-MoS2 is an effective strategy to lower overpotential for hydrogen evolution reaction (HER). In acidic media onset potential with intercalated ions lowered by ∼60 mV relative pristine (onset ∼180 mV). Density functional theory (DFT) calculations a lowering in Gibbs free energy H-adsorption (ΔGH) on these structures intercalant-free 1T-MoS2. The DFT suggest Na+ results ΔGH close zero. Consistent...

Operation of Li-ion batteries below −20 °C is hindered by low electrolyte conductivity and sluggish solid-state diffusion in electrodes. Li metal anodes show promise for low-temperature operation, but few compositions exhibit high at reduced temperature while also allowing electrodeposition/stripping with Coulombic efficiency. Here, we that the efficiency can be substantially improved temperatures (−60 °C) tailoring solid-electrolyte interphase (SEI) structure through use two classes...

While Li-ion batteries are known to fail at temperatures below -20 °C, very little is regarding the low-temperature behavior of next-generation high-capacity electrode materials. The lithium metal anode particular interest for high-energy battery chemistries, but improved understanding and control over its electrochemical nanoscale interfacial in diverse conditions necessary. Here, we investigate deposition/stripping, morphology evolution, solid-electrolyte interphase (SEI) structure...

Nonaqueous sodium-based batteries are ideal candidates for the next generation of electrochemical energy storage devices. However, despite promising performance at ambient temperature, their low-temperature (e.g., < 0 °C) operation is detrimentally affected by increase in electrolyte resistance and solid interphase (SEI) instability. Here, to circumvent these issues, we propose specific formulations comprising linear cyclic ether-based solvents sodium trifluoromethanesulfonate salt that...

Vertically aligned interlayer expanded (IE) MoS₂ on a Ti₃C₂T_x (MXene) support as an efficient electrocatalytic HER catalyst.

We investigated the dependence of electrocatalytic activity for oxygen evolution reaction (OER) on interlayer distance five compositionally distinct layered manganese oxide nanostructures. Each individual electrocatalyst was assembled with a different alkali metal intercalated between two nanosheets (NS) to form bilayer structure. Manganese NS were synthesized via exfoliation material, birnessite. Atomic force microscopy used determine heights catalysts. The spacing supported bilayers...

Two-dimensional (2D) nanomaterials have attracted considerable attention in biomedical and environmental applications due to their antimicrobial activity. In the interest of investigating primary mode-of-action 2D nanomaterials, we studied properties MnO2 MoS2, toward Gram-positive Gram-negative bacteria. Bacillus subtilis Escherichia coli bacteria were treated individually with 100 μg/mL randomly oriented vertically aligned for ∼3 h dark. The MoS2 grown on sheets graphene oxide, reduced...

Abstract We report a synthetic method to enhance the electrocatalytic activity of birnessite for oxygen evolution reaction (OER) by intercalating Ni 2+ ions into interlayer region. Electrocatalytic studies showed that nickel (7.7 atomic %)‐intercalated exhibits an overpotential ( η ) 400 mV OER at anodic current 10 mA cm −2 . This is significantly lower than values ≈700 mV) and active catalyst β‐Ni(OH) 2 ≈550 mV). Molecular dynamics simulations suggest competition among interactions between...

We show that the activity of cobalt for oxygen evolution reaction (OER) can be enhanced by confining it in interlayer region birnessite (layered manganese oxide). The intercalation was verified employing state-of-the-art characterization techniques such as X-ray diffraction, Raman spectroscopy, and electron microscopy. It is demonstrated Co2+/birnessite electrocatalyst reach 10 mA cm–2 at an overpotential 360 mV with near-unity Faradaic efficiency. This lower than which achieved using a pure...

We present a combined experimental and theoretical study to demonstrate that the electrocatalytic activity of NiFe layered double hydroxides (NiFe LDHs) for oxygen evolution reaction (OER) can be significantly enhanced by systematic cobalt incorporation using coprecipitation and/or intercalation. Electrochemical measurements show modified LDH possesses an OER relative pristine LDH. The Co-modified exhibits overpotentials in range 290-322 mV (at 10 mA cm-2), depending on degree content. best...

Solid-state electrolyte separators play a critical role in improving energy density, charging rate, and safety next-generation batteries; however, controlling the interface between Li-metal separator continues to be challenging. Here, using garnet-type Li7La3Zr2O12 (LLZO) ceramic solid electrolyte, we show that sputter-coated thin metallic interlayers (∼300 nm of gold) combination with controlled discharge rates (0.3 mA/cm2) practical levels external pressure (0.7 MPa) vital roles mitigating...

We report a synthetic method to increase the catalytic activity of birnessite toward water oxidation by intercalating copper in interlayer region layered manganese oxide. Intercalation copper, verified XRD, XPS, ICP, and Raman spectroscopy, was accomplished exposing suspension Cu+-bearing precursor molecule that underwent disproportionation solution yield Cu0 Cu2+. Electrocatalytic studies showed Cu-modified exhibited an overpotential for ∼490 mV (at 10 mA/cm2) Tafel slope 126 mV/decade...

The electrocatalytic reduction of CO₂ to CO on the Mo₂C and Ti₃C₂ MXenes. DFT calculations show that surface oxygen vacancies are reaction active sites.

A new dual-salt liquid electrolyte is developed that enables the reversible operation of high-energy sodium-metal-based batteries over a wide range temperatures down to −50 °C.

Lithium–metal batteries with solid electrolyte separators promise improvements in energy density, fast charge capability, and safety. However, the lack of control electrolyte–lithium–metal interface continues to impede development. Interlayers between lithium–metal are reported improve performance but have limitations due stability, rate limitations, use undesirable elements (e.g., Ag, Au). Here, we show that a thin layer abundant metal Sn provides required stability transport properties...

Significance We propose, and preliminarily confirm with experiments, a theoretical model to understand various structure–performance dependences of layered-structure birnessite as an oxygen evolution reaction (OER) catalyst. Besides the well-accepted importance Mn(III), we emphasize critical nonuniform distribution Mn(III) OER catalytic activity. Such contributes reduction overpotential by building internal potential step. further propose small polaron common concept link fields catalysis...

The effect on the electrocatalytic oxygen evolution reaction (OER) of cobalt incorporation into metal oxide sheets layered manganese birnessite was investigated. Birnessite and cobalt-doped were characterized by X-ray diffraction (XRD), photoelectron spectroscopy (XPS), Raman spectroscopy, conductivity measurements. A cobalt:manganese ratio 1:2 resulted in most active catalyst for OER. In particular, overpotential (η) OER 420 mV, significantly lower than η = 780 mV associated with absence...

Lithium metal and lithium-rich alloys are high-capacity anode materials that could boost the energy content of rechargeable batteries. However, their development has been hindered by rapid capacity decay during cycling, which is driven substantial structural, morphological, volumetric transformations these interfaces experience charge discharge. During transformations, interplay between chemical/structural changes solid mechanics plays a defining role in determining electrochemical...

Abstract Energy efficient hydrogen production via electrochemical and/or photoelectrochemical water splitting holds significant potential for clean and sustainable energy. Toward this end, a amount of research has been focused on developing active earth abundant metal catalysts the evolution reaction (HER) use in acidic alkaline media. Here, we report an metal‐based catalyst HER under conditions. The consisting Co, Mo P had similar activity as precious platinum conditions used study. Co−Mo−P...

Described is a synthetic method to enhance the electrocatalytic activity of layered manganese oxide, birnessite, for oxygen evolution reaction (OER) through development Mn/Co/Fe ternary phase. The phase was synthesized by simultaneous doping Co3+ into oxide lattice and intercalation Fe2+ within interlayer region birnessite (KxFe[Co0.16Mn0.84O2]). material characterized X-ray diffractometry, electron microscopy, photoelectron, energy dispersive, Raman spectroscopies electrochemical analysis....

A chemical synthesis for the cobalt pertelluride mineral mattagamite is reported. Synthetic nanocrystalline was investigated electrochemical water oxidation and showed catalytic activity. Electrochemical occurred at an overpotential of 380 mV 10 mA/cm−2 with a Tafel slope 58 mV/decade Faradaic efficiency 96% turnover frequency 0.021 s–1 0.5 V.

The effect of simulated solar radiation on the oxidation arsenite [As(III)] to arsenate [As(V)] layered manganese oxide, birnessite, was investigated. Experiments were conducted where birnessite suspensions, under both anoxic and oxic conditions, irradiated with in presence As(III) at pH 5, 7, 9. X-ray absorption spectroscopy (XAS) used determine nature adsorbed product surface birnessite. light irradiation occurred a rate that faster than absence 5. At 7 9, As(V) production significantly...

Abstract We report a synthetic method to enhance the electrocatalytic activity of birnessite for oxygen evolution reaction (OER) by intercalating Ni 2+ ions into interlayer region. Electrocatalytic studies showed that nickel (7.7 atomic %)‐intercalated exhibits an overpotential ( η ) 400 mV OER at anodic current 10 mA cm −2 . This is significantly lower than values ≈700 mV) and active catalyst β‐Ni(OH) 2 ≈550 mV). Molecular dynamics simulations suggest competition among interactions between...

Abstract A metallic MoS 2 (M−MoS ) catalyst containing either Ni or Co with excellent activity for the hydrogen evolution reaction (HER) under alkaline electrocatalytic conditions was investigated. To synthesize 3d transition metal electrocatalysts, 1–20 at.% substituted into lattice of orthorhombic MoO 3 and doped oxide precursor sulfided converted to Ni/M−MoS Co/M−MoS . Raman spectroscopy photoelectron were used verify that metallic‐like 1T′ phase dichalcogenide. The 10 (10 electrochemical...

Abstract Lithium‐ion batteries (LIBs) show poor performance at temperatures below 0 °C due to sluggish reaction kinetics, hindered diffusion, and electrolyte freezing. Materials that alloy with lithium offer higher specific capacity than graphite anodes are studied extensively room temperature, but their low‐temperature behavior is not well understood. Here, the electrochemical transformation of three materials (antimony, silicon, tin) investigated. It shown antimony particularly suited for...