Visible-light-active and photostable, multilayered materials and their preparation method based on surface-modified titanium(IV) oxide have been invented.

Compositions and methods for the catalysis of methane pyrolysis. Compositions include a catalyst system that includes a medium entropy alloy particle and a support. Methods include catalyzing the pyrolysis of methane using the catalyst system.

The purpose of the present invention is to provide a catalyst support with which it is possible to produce a high-quality fibrous carbon nanostructure. The purpose of the present invention is to provide a catalyst support used when producing a fibrous carbon nanostructure, the catalyst support comprising a carrier and a catalyst layer formed on the carrier, the catalyst layer including a metal-containing compound, and the difference YI in yellowness expressed by the formula being 3-20, where YI.sub.A is the yellowness of the carrier, and YI.sub.B is the yellowness of the catalyst support. YI=YI.sub.BYI.sub.A.