A nanocomposite has a core-shell structure with an outer shell and an inner core. The outer shell is a graphitized carbon film, and the inner core contains nickel oxide and alumina, with a nickel oxide content of 59%-80%, an alumina content of 19%-40%, and a carbon content of not more than 1%, based on the total weight of the nanocomposite. The process for catalytic combustion of volatile organic compounds may utilize the nanocomposite as a catalyst.

Provided is an exhaust gas purification catalyst that suppresses phosphorus poisoning and improves long-term durability. The exhaust gas purification catalyst includes a phosphorus collection layer and a catalyst layer containing at least one precious metal element M.sup.p selected from the group consisting of Pt, Pd, and Rh, wherein the phosphorus collection layer is arranged on the upper layer side and/or the upstream side with respect to the catalyst layer; the phosphorus collection layer contains a composite oxide containing Al and an alkaline earth metal element M.sup.a that includes Mg and that may include at least one selected from the group consisting of Ca, Sr, and Ba, and having a cubic spinel structure belonging to the space group Fd-3m; the composite oxide has a M.sup.a/Al molar ratio in a range of 0.02 or more and 0.60 or less; and the composite oxide has a peak derived from the cubic spinel structure belonging to the space group Fd-3m of the composite oxide between a diffraction angle 2x.sub.M.sup.a.sub.O that is a position of a peak derived from an alkaline earth metal oxide M.sup.aO and a diffraction angle 2x.sub.Al2O3 that is a position of a peak derived from an aluminum oxide Al.sub.2O.sub.3 in an X-ray diffraction spectrum.