Provided are a semiconductor material based on metal nanowires and a porous nitride, and a preparation method thereof. The semiconductor material includes: a substrate; a buffer layer formed on the substrate; and a composite material layer formed on the buffer layer the composite material layer includes: a transverse porous nitride template layer; and a plurality of metal nanowires filled in pores of the transverse porous nitride template layer.

There is provided a method of preparing a photoelectrochemical and electrochemical electrode catalyst, the method including preparing a metal oxide-based electrode, introducing a phosphate layer on a surface of the metal oxide-based electrode; and converting the phosphate layer into an oxyhydroxide layer by performing electrochemical activation on the phosphate layer. The efficiency of selective oxidation reaction of ammonia in wastewater may be improved.

The present disclosure provides a catalyst, its preparation and uses thereof, the catalyst comprising a conductive substrate coated by at least two layers including a proximal layer and a distal layer wherein said proximal layer comprises a proximal metal composition and said distal layer comprise a distal metal composition, the proximal metal composition being different from the distal metal composition; wherein said proximal metal composition comprises a metallic M and said distal metal composition comprise a combination of two or more different metal complexes, each having a formula M.sub.xL.sub.y, wherein M, which may be the same or different in said two or more metal complexes, represents a metal atom; L, which may be the same or different in said two or more metal complexes, represents a moiety comprising at least one atom selected from the group consisting of oxygen (O), phosphorous (P), boron (B) and nitrogen (N); x represents any value between (1) and (6); and y represents any value between (1) and (6); and wherein said metal atom of metallic M and said metal atom in M.sub.xL.sub.y may be the same or different metal atom.

A base material includes a base layer. The base layer includes a structured surface. The base layer includes a transition metal and a transition metal oxide, and a sum of the transition metal and a transition metal oxide accounts for at least 90 wt. % of the base layer. The transition metal oxide is concentratedly distributed on the structured surface. The base material is flexible in at least one direction, and has a bending angle of not less than 90 when being bent.

A palladium copper (PdCu) single-atom alloy (SAA) catalyst for nitrate reduction, as well as a method of nitrate reduction using the same, are provided. The PdCu SAA catalyst comprises a Cu substrate and at least one isolated Pd atom dispersed in a surface of the Cu substrate. The method of nitrate reduction comprises contacting the PdCu SAA catalyst with a nitrate source to selectively produce ammonia. The nitrate source can be waste water.

There is provided a catalyst composition including a hydrogen oxidation catalyst and an oxygen reduction catalyst. Heat exchange reactors including the catalyst are also provided. The catalyst is adapted for low temperature activation of a hydrogen combustion reaction.