A catalyst that includes heterogeneous metal carbide nanomaterials and a novel preparation method to synthesize the metal carbide nanomaterials under relatively mild conditions to form an encapsulated transition metal and/or transition metal carbide nanoclusters in a support and/or binder. The catalyst may include confined platinum carbide nanoclusters. The preparation may include the treatment of encapsulated platinum nanoclusters with ethane at elevated temperatures. The catalysts may be used for catalytic hydrocarbon conversions, which include but are not limited to, ethane aromatization, and for selective hydrogenation, with negligible green oil production.

A catalyst that includes heterogeneous metal carbide nanomaterials and a novel preparation method to synthesize the metal carbide nanomaterials under relatively mild conditions to form an encapsulated transition metal and/or transition metal carbide nanoclusters in a support and/or binder. The catalyst may include confined platinum carbide nanoclusters. The preparation may include the treatment of encapsulated platinum nanoclusters with ethane at elevated temperatures. The catalysts may be used for catalytic hydrocarbon conversions, which include but are not limited to, ethane aromatization, and for selective hydrogenation, with negligible green oil production.

A bifunctional catalyst for example for conversion of oxygenates, said bifunctional catalyst comprising zeolite, alumina binder, Zn and P, wherein Zn is present at least partly as ZnAl.sub.2O.sub.4.

The invention is directed to hollow zeolite encapsulated metal particle catalysts where the metal particle is contained in the hollow of the zeolite, their preparation method by depositing metal particle precursors and subsequent removal of said metal particle precursors from the surface of the hollow zeolite while retaining those in the cavity of the hollow zeolite, and the catalysts' use in selective benzene alkylation.

The invention relates to a composition that contains a first semiconductor SC1, particles that comprise one or more element(s) M in the metal state selected from among an element of groups IVB, VB, VIB, VIIB, VIIIB, IB, IIB, IIIA, IVA and VA of the periodic table, and a second semiconductor SC2 that comprises cerium oxide, with said first semiconductor SC1 being in direct contact with said particles that comprise one or more element(s) M in the metal state, with said particles being in direct contact with said second semiconductor SC2 that comprises cerium oxide in such a way that the second semiconductor SC2 covers at least 50% of the surfaces of the particles that comprise one or more element(s) M in the metal state. The invention also relates to its preparation method as well as its application of photocatalysis.

Shaped porous carbon products and processes for preparing these products are provided. The shaped porous carbon products can be used, for example, as catalyst supports and adsorbents. Catalyst compositions including these shaped porous carbon products, processes of preparing the catalyst compositions, and various processes of using the shaped porous carbon products and catalyst compositions are also provided.

A composition consisting essentially of a perovskite crystalline structure, the composition comprising: ions of a first metal M.sup.1 which occupies an A-site of the perovskite crystalline structure; ions of a second metal M.sup.2 which occupies a B-site of the perovskite crystalline structure, M.sup.2 having two oxidation states capable of forming a redox couple suitable for reversibly catalyzing an oxygen reduction reaction (ORR) and an oxygen evolution reaction (OER); ions of a third metal M.sup.3 at least a portion of which substitutes for M.sup.1 in the A-site of the perovskite crystalline structure, and at least a portion of which optionally also substitutes for M.sup.2 in the B-site of the perovskite crystalline structure, at least some of the atoms M.sup.3 having a different oxidation state to the atoms M.sup.1; and atoms of an element X, which is a chalcogen; wherein the metal ions M.sup.1, M.sup.2 and M.sup.3 are present in the atomic ratios (a) or (b): (a) 25 to 49.9 atomic % M.sup.1, 30 to 60 atomic % M.sup.2, and 5 to 45 atomic % M.sup.3; (b) 10 to 30 atomic % M.sup.1, 50.1 to 60 atomic % M.sup.2, and 25 to 45 atomic % M.sup.3; each expressed as a percentage of the total metal ions in the composition excluding oxygen; wherein the presence of the M.sup.3 ions causes a change in the oxidation state of some of the M.sup.2 ions in the structure, thereby creating the redox couple suitable for reversibly catalyzing the ORR and OER.

Provided is a catalyst having a core-shell structure (which employs a core comprised of a highly electrochemically stable, relatively inexpensive material and thereby reduces the amount of platinum used, while providing a better cost/performance ratio in catalytic activity as compared to when platinum particles are used as a catalyst) for use in an oxygen reduction reaction (cathode reaction in a fuel cell), and to provide an oxygen reduction method using the catalyst. Provided is a core-shell catalyst for use for an oxygen reduction reaction, including: a core that is comprised of silver; and a shell layer that comprised of platinum, the shell layer being comprised of platinum atoms constituting a (111) plane of or a (001) plane of a face centered cubic lattice, in the shell layer, a nearest neighbor platinum-platinum interatomic distance falling within the range of from 2.81 {acute over ()} to 2.95 {acute over ()}.

The manufacturing method provided by the present invention provides a powder material substantially comprising AgPd core-shell particles consisting of Ag core particles containing silver as a principal constituent element and a Pd shell containing palladium as a principal constituent element covering at least part of the surface of the Ag core particles, wherein hydroquinone and/or a quinone is attached to the surface of the AgPd core-shell particles.

Typically, when the powder material is in a dispersed state in a specific medium, a Z average particle diameter (D.sub.DLS) based on the dynamic light scattering (DLS) method is 0.1 m to 2 m, and the polydispersity index (PDI) based on the dynamic light scattering method is 0.4 or lower.

Catalysts, catalytic systems and related synthetic methods for in situ production of H.sub.2O.sub.2 and use thereof in reaction with oxidizable substrates.