The present invention relates to a method for dissolving metals by photocatalysis. A metal-containing material to be dissolved is dispersed in a mixed solution of photocatalyst-containing cyanide and organic chloride; then, a photocatalyst is added; next, an oxygen-containing gas or a substance which is capable of generating oxygen is introduced; and irradiation is applied for a period of time to dissolve metals. Compared with the prior method, the present invention is advantageous in moderate reaction condition, energy conservation, environmental protection, low cost, and convenient operation, and is suitable for mass industrial treatment on metal dissolution.

Disclosed are a catalyst and a preparation method therefor, the catalyst being able to maintain a high production yield of C8 aromatic hydrocarbons in the process of converting a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through disproportionation/transalkylation/dealkylation while reducing a content of ethylbenzene in the products.

Disclosed are a catalyst and a preparation method therefor, the catalyst being able to maintain a high production yield of C8 aromatic hydrocarbons in the process of converting a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through disproportionation/transalkylation/dealkylation while reducing a content of ethylbenzene in the products.

A novel synthetic crystalline molecular sieve material, designated boron SSZ-121 is provided. The boron SSZ-121 can be synthesized using 1,3-bis(1-adamantyl)imidazolium cations as a structure directing agent. The boron SSZ-121 may be used in organic compound conversion reactions and/or sorptive processes.

A novel synthetic crystalline molecular sieve material, designated boron SSZ-121 is provided. The boron SSZ-121 can be synthesized using 1,3-bis(1-adamantyl)imidazolium cations as a structure directing agent. The boron SSZ-121 may be used in organic compound conversion reactions and/or sorptive processes.

Disclosed is a catalyst for oxygen reduction and evolution reactions. The catalyst is in the form of nickel sulfide (NiS.sub.2) nanosheets. NiS.sub.2 molecules are cross-linked and oriented two-dimensionally in the NiS.sub.2 nanosheets. Also disclosed is a method for producing the catalyst.

Disclosed is a catalyst for oxygen reduction and evolution reactions. The catalyst is in the form of nickel sulfide (NiS.sub.2) nanosheets. NiS.sub.2 molecules are cross-linked and oriented two-dimensionally in the NiS.sub.2 nanosheets. Also disclosed is a method for producing the catalyst.

A catalyst for purification of exhaust gas containing a phosphorus compound includes: a lower catalyst layer containing at least one of noble metal provided on a refractory three-dimensional structure; and an upper catalyst layer at an inflow side of exhaust gas and an upper catalyst layer at an outflow side of exhaust gas provided on a surface of the lower catalyst layer. The upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side have different concentrations of noble metal. The catalyst has an intermediate zone with a length of 3 to 23% of the overall length of the refractory three-dimensional structure provided between the upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side. The intermediate zone starts from a position 10 to 38% from an end face of the catalyst at the inflow side of exhaust gas.

A catalyst for purification of exhaust gas containing a phosphorus compound includes: a lower catalyst layer containing at least one of noble metal provided on a refractory three-dimensional structure; and an upper catalyst layer at an inflow side of exhaust gas and an upper catalyst layer at an outflow side of exhaust gas provided on a surface of the lower catalyst layer. The upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side have different concentrations of noble metal. The catalyst has an intermediate zone with a length of 3 to 23% of the overall length of the refractory three-dimensional structure provided between the upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side. The intermediate zone starts from a position 10 to 38% from an end face of the catalyst at the inflow side of exhaust gas.

A method of fabricating a semiconductor device includes plasma etching a portion of a plurality of metal dichalcogenide films comprising a compound of a metal and a chalcogen disposed on a substrate by applying a plasma to the plurality of metal dichalcogenide films. After plasma etching, a chalcogen is applied to remaining portions of the plurality of metal dichalcogenide films to repair damage to the remaining portions of the plurality of metal dichalcogenide films from the plasma etching. The chalcogen is S, Se, or Te.