The exhaust gas purification device includes a substrate, a first catalyst layer, and a second catalyst layer. The substrate includes an upstream end, a downstream end, and a porous partition wall defining a plurality of cells extending between the upstream end and the downstream end. The plurality of cells include an inlet cell opening at the upstream end and sealed at the downstream end, and an outlet cell adjacent to the inlet cell sealed at the upstream end and opening at the downstream end. The first catalyst layer is disposed on a surface of the partition wall in an upstream region. In a downstream region, the second catalyst layer is disposed inside the partition wall, and a second catalyst-containing wall including the partition wall and the second catalyst layer has a porosity of 35% or more.

The exhaust gas purifying catalyst presented here includes a substrate and a catalyst coat layer formed on the surface of the substrate. The catalyst coat layer is formed in a laminate structure having two layers, with a first layer being nearer to the surface of the substrate and a second layer being relatively further from this surface. The second layer includes a carrier and a noble metal supported on the carrier. The first layer is a noble metal-free layer that does not contain a noble metal but does contain an OSC material having oxygen storage capacity.

A core-shell nanoparticle is provided that includes a core comprising a first isotope of an element; an isolation layer surrounding the core; and a shell layer surrounding the isolation layer, wherein the shell layer comprises a second isotope of the element, with the first isotope being different than the second isotope. Methods are also provided for forming such core-shell nanoparticles.

According to various aspects and exemplary embodiments of the present disclosure, ultra-small catalyst particles having extremely high reactivity may be synthesized in single-atom or single-molecule state. When the ultra-small-sized single-atom or single-molecule catalyst is used, the use of metal raw materials can be minimized and, at the same time, catalytic activity may be maximized through maximized reactivity of the single-atom or single-molecule catalyst.

A process for producing a Fischer-Tropsch synthesis catalyst according to the present invention comprises a step of calcining a carrier precursor containing silica calcined at a temperature T.sub.1 and a zirconium compound at a temperature T.sub.2 to obtain a carrier; and a step of calcining a catalyst precursor containing the carrier and a cobalt compound and/or a ruthenium compound at a temperature T.sub.3, wherein the content of the zirconium compound in the carrier precursor is 0.01 to 7% by mass in terms of zirconium oxide based on the total mass of the catalyst, and T.sub.1, T.sub.2, and T.sub.3 satisfy conditions represented by expressions (1) to (3):
T.sub.1≧T.sub.3  (1)
250° C.≦T.sub.2≦450° C.  (2)
250° C.≦T.sub.3≦450° C.  (3).

The present invention relates to a selective catalytic reduction catalyst for the treatment of an exhaust gas of a combustion engine, the catalyst comprising a substrate comprising an inlet end, an outlet end, a substrate axial length extending from the inlet end to the outlet end and a plurality of passages defined by internal walls of the substrate extending therethrough; a coating disposed on the substrate (i), the coating comprising a first non-zeolitic oxidic material comprising aluminum, an 8-membered ring pore zeolitic material comprising one or more of copper and iron, and a second non-zeolitic oxidic material comprising cerium and one or more of zirconium, aluminum, silicon, lanthanum, niobium, iron, manganese, titanium, tungsten, copper, molybdenum, neodymium, cobalt, chromium, tin and praseodymium; wherein at least 65 weight-% of the coating consist of the 8-membered ring pore zeolitic material comprising one or more of copper and iron.

An exhaust gas purification device includes a substrate including an upstream end and a downstream end and having a length Ls; a first containing Pd particles, extending between the upstream end and a first position, and being in contact with the substrate; a second containing Rh particles, extending between the downstream end and a second position, and being in contact with the substrate; and a third catalyst layer containing Rh particles, extending between the upstream end and a third position, and being in contact with at least the first catalyst layer, wherein an average of a Rh particle size distribution is from 1.0 to 2.0 nm, and a standard deviation of the Rh particle size distribution is 0.8 nm or less in each of the second catalyst layer and the third catalyst layer.

Described are compositions and catalytic articles comprising both a first molecular sieve promoted with copper and a second molecular sieve promoted with iron, the first and second molecular sieves having a d6r unit and the first molecular sieves having cubic shaped crystals with an average crystal size of about 0.5 to about 2 microns. The weight ratio of the copper-promoted molecular sieve to the iron-promoted molecular sieve can be about 1:1 to about 4:1. The catalytic articles are useful in methods and systems to catalyze the reduction of nitrogen oxides in the presence of a reductant.

According to various aspects and embodiments, multilayer particles having an irregular surface architecture and methods of making the same are disclosed.

Disclosed are metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles having high dispersibility. The metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles having high dispersibility can be obtained by containing metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles, which are capable of splitting water under visible light irradiation, and a phosphoric acid polymer that is adsorbed on the surface of the particles. Further, because these particles have high photocatalytic activity under visible light irradiation, splitting water by using these particles can generate hydrogen and/or oxygen with high efficiency.