Abstract:
Electrodeposition involving an electrolyte having a surface-smoothing additive can result in self-healing, instead of self-amplification, of initial protuberant tips that give rise to roughness and/or dendrite formation on the substrate and/or film surface. For electrodeposition of a first conductive material (C1) on a substrate from one or more reactants in an electrolyte solution, the electrolyte solution is characterized by a surface-smoothing additive containing cations of a second conductive material (C2), wherein cations of C2 have an effective electrochemical reduction potential in the solution lower than that of the reactants.
Abstract:
Disclosed herein is a method for dissolving ion exchange membranes to provide dissolved polymers, particularly at low temperatures and/or pressures, that can be recast to regenerate ion exchange membranes exhibiting reduced defects compared to the initial ion exchange membrane. In some aspects of the disclosure, the polymer exchange membranes include a perfluorosulfonic acid polymer. In some aspects of the disclosure, the method involves dissolving the membranes in one or more aprotic solvents, particularly at temperatures below 80° C.
Abstract:
Aqueous electrolytes comprising fluorenone/fluorenol derivatives are disclosed. The electrolyte may be an anolyte for an aqueous redox flow battery. In some embodiments, the compound, or salt thereof, has a structure according to any one of formulas I-III where Q1-Q4 independently are CH, C(R1) or N, wherein 0, 1, or 2 of Q1-Q4 are N; Q5-Q8 independently are CH, C(R2), or N, wherein 0, 1, or 2 of Q5-Q8 are N; Y is C═O or C(H)OH; R1 and R2 independently are an electron withdrawing group; n is an integer >1; and x and y independently are 0, 1, 2, 3, or 4, where at least one of x and y is not 0.
Abstract:
Catalysts comprising MoP and MoP2 are disclosed, wherein the catalyst is a composite. The catalyst may have a molar ratio of MoP:MoP2 within a range of 5:95 to 95:5. The catalyst may be used as a cathode active material for hydrogen generation from neutral pH solutions, such as wastewater or seawater. Methods of making the catalyst also are disclosed.
Abstract:
Described herein are systems and methods of storing and delivering electrical using hydrogen at low-cost and for long-durations. The systems and methods use energy-bearing redox pairs that electrochemically bear energy through decoupled hydrogen and oxygen consumption and/or evolution reactions, which are typically associated with fuel cells. Each species of the energy-bearing redox pair is associated with a standard electrode potential within a water electrolysis voltage window for the electrolyte solution. Electrical energy delivery, hydrogen generation, electrolyte regeneration, or combinations thereof can be performed by logically or physically separated unit operations in a continuous manner, batch manner, or semi-batch manner facilitated by the energy-bearing redox pair.
Abstract:
Embodiments of a solid-state electrolyte comprising magnesium borohydride, polyethylene oxide, and optionally a Group IIA or transition metal oxide are disclosed. The solid-state electrolyte may be a thin film comprising a dispersion of magnesium borohydride and magnesium oxide nanoparticles in polyethylene oxide. Rechargeable magnesium batteries including the disclosed solid-state electrolyte may have a coulombic efficiency ≧95% and exhibit cycling stability for at least 50 cycles.
Abstract:
Disclosed are preformed solid electrolyte interface (SEI) film graphite electrodes in lithium-sulfur based chemistry energy storage systems and methods of making the preformed SEI films on graphite electrodes to expand the use of graphite-based electrodes in previously non-graphite anode energy systems, such as lithium-sulfur battery systems. Also disclosed are lithium-ion sulfur battery systems comprising electrolytes that do not include an alkyl carbonate, such as those that do not include EC, and graphite anodes having preformed alkyl carbonate, such as EC-based SEI films.
Abstract:
Nanostructured bismuth materials can be utilized as an insertion material in electrodes for magnesium energy storage devices to take advantage of short diffusion lengths for Mg2+. The result can be a significantly increased charge/discharge rates and/or improved cycling stabilities. In one example, an energy storage device has magnesium as an electroactive species, an electrolyte salt containing magnesium, and an anode having bismuth nanostructures. The bismuth nanostructures have at least one dimension that is less than or equal to 25 nm. At least a portion of the magnesium is reversibly inserted into, and extracted from, the anode during discharging and charging states, respectively.
Abstract:
The performance of sodium-based energy storage devices can be improved according to methods and devices based on surface-driven reactions between sodium ions and functional groups attached to surfaces of the cathode. The cathode substrate, which includes a conductive material, can provide high electron conductivity while the surface functional groups can provide reaction sites to store sodium ions. During discharge cycles, sodium ions will bind to the surface functional groups. During charge cycles, the sodium ions will be released from the surface functional groups. The surface-driven reactions are preferred compared to intercalation reactions.
Abstract:
Described herein are systems and methods of hydrogen generation and electrolyte regeneration as independent operations in separate redox flow cells. The operations can be decoupled by using an energy-bearing redox pair that electrochemically bears energy facilitating flexible, efficient hydrogen generation. In one example, the hydrogen generation redox flow cell can include a liquid, energy-bearing electrolyte solution in which at least one species of an energy-bearing redox pair is dissolved, to decouple the hydrogen evolution reaction from the reaction at the opposite electrode (e.g., the oxygen evolution reaction of conventional direct water electrolysis). Each species of the energy-bearing redox pair is associated with a standard electrode potential within the water electrolysis window.