Embodiments of the present disclosure pertain to electrocatalysts that include a surface and a plurality of catalytically active sites associated with the surface. The catalytically active sites include individually dispersed metallic atoms that are associated with heteroatoms. In some embodiments, the surface includes graphene oxide, the heteroatoms include nitrogen, and the metallic atoms include cobalt. Additional embodiments of the present disclosure pertain to methods of mediating an electrocatalytic reaction by exposing a precursor material to an electrocatalyst of the present disclosure. In some embodiments, the electrocatalytic reaction is a hydrogen evolution reaction that results in the formation of molecular hydrogen from the precursor material. Further embodiments of the present disclosure pertain to methods of making the electrocatalysts of the present disclosure by associating a surface with heteroatoms and metallic atoms.

A process for the preparation of a membrane electrode assembly comprising providing, in the following layer order, (I) a green supporting electrode layer comprising a composite of a mixed metal oxide and Ni oxide; (IV) a green mixed metal oxide membrane layer; and (V) a green second electrode layer comprising a composite of a mixed metal oxide and Ni oxide; and sintering all three layers simultaneously.

The invention pertains to the field of catalysts. Disclosed is a method for preparing an oxygen reduction catalyst employing graphite of a negative electrode of a waste battery. The method comprises the following steps: (1) recovering graphite slag from a waste battery, then performing heat treatment on the graphite slag; (2) performing ball-milling and mixing on the treated graphite slag, an iron salt, and a nitrogenous organic compound to acquire a catalyst precursor; (3) performing carbonization treatment on the catalyst precursor in an inert gas atmosphere to acquire a carbon-based mixture comprising iron and nitrogen; and (4) dissolving the carbon-based mixture comprising iron and nitrogen in an acid solution, performing filtration and drying, performing carbonization treatment again in an inert gas atmosphere, so as to acquire an oxygen reduction catalyst employing graphite of a negative electrode of a waste battery. The invention uses graphite slag generated in a recovery process of a waste lithium ion battery as a raw material. The graphite slag is widely available, and has low costs. The invention reduces environmental pollution, and has economic benefits.

The Ce—H.sub.2 redox flow cell is optimized using commercially-available cell materials. Cell performance is found to be sensitive to the upper charge cutoff voltage, membrane boiling pretreatment, methanesulfonic-acid concentration, (+) electrode surface area and flow pattern, and operating temperature. Performance is relatively insensitive to membrane thickness, Cerium concentration, and all features of the (−) electrode including hydrogen flow. Cell performance appears to be limited by mass transport and kinetics in the cerium (+) electrode. Maximum discharge power of 895 mW cm.sup.−2 was observed at 60° C.; an energy efficiency of 90% was achieved at 50° C. The Ce—H.sub.2 cell is promising for energy storage assuming one can optimize Ce reaction kinetics and electrolyte.

Provided is an electrode catalyst that can exhibit sufficient performance, is suitable for mass production, and is suitable for reducing production costs, even when containing a relatively high concentration of chlorine. The electrode catalyst has a core-shell structure including a support; a core part that is formed on the support; and a shell part that is formed so as to cover at least one portion of the surface of the core part. A concentration of bromine (Br) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 500 ppm or less, and a concentration of chlorine (Cl) species of the electrode catalyst as measured by X-ray fluorescence (XRF) spectroscopy is 8,500 ppm or less.

The present invention relates to stable catalyst ink formulations comprising am electrospinning polymer selected from halogen-comprising polymers. The present invention further relates to electrospinning of such ink formulation, to the so-obtained electrospun fibrous mat as well as to articles comprising such electrospun fibrous mat.

The present invention relates to a process for preparing a supported catalytic material, wherein the said process comprises a step of heating a precursor of support material which has been impregnated with a mixture of chemical precursors, wherein the said mixture includes a nitrogen-containing reducing reagent as a precursor and a transition-metal-containing compound as a precursor.

Compositions comprised of a tin film, coated by a shell of less than 50 nm thick made of palladium and tin in a molar ratio ranging from 1:4 to 3:1, respectively, are disclosed. Uses of the compositions as an electro-catalyst e.g., in a fuel cell, and particularly for the oxidation of various materials are also disclosed.

A composition comprised of a tin (Sn) or lead (Pb) film, wherein the film is coated by a shell, wherein the shell: (a) is comprised of an active metal, and (b) is characterized by a thickness of less than 50 nm, is discloses herein. Further disclosed herein is the use of the composition for the oxidation of e.g., methanol, ethanol, formic acid, formaldehyde, dimethyl ether, methyl formate, and glucose.

Parasitic reactions, such as evolution of hydrogen at the negative electrode, can occur under the operating conditions of flow batteries and other electrochemical systems. Such parasitic reactions can undesirably impact operating performance by altering the pH and/or state of charge of one or both electrolyte solutions in a flow battery. Electrochemical balancing cells can allow adjustment of electrolyte solutions to take place. Electrochemical balancing cells suitable for placement in fluid communication with both electrolyte solutions of a flow battery can include: a first chamber containing a first electrode, a second chamber containing a second electrode, a third chamber disposed between the first chamber and the second chamber, a cation-selective membrane forming a first interface between the first chamber and the third chamber, and a bipolar membrane, a cation-selective membrane, or a membrane electrode assembly forming a second interface between the second chamber and the third chamber.