Owning to their unique structures and multi-functionalities, the core-shell structured nanomaterials are receiving great attention in recent years, and being widely used in various catalytic processes. The purpose of this review is to highlight the recent achievements in fabrication and application of core-shell nanostructures (i.e., metal core@metal shell, metal core@oxide shell, metal core@carbon shell, metal core@polymer, and metal core@zeolite shell) in catalytic chemistry. The influences of assembled structures and resulting electronic properties on catalytic performance as well as catalyst durability are discussed. In view of the new research findings, the concept of nanoreactor with the yolk/shell structure and its role in catalytic reactions are outlined. At the end of the article, a summary and outlook of these novel materials with respect to controlled synthesis and potential applications are provided.

Contents
1 Introduction
2 Progress in fabrication and application of core-shell structured nanomaterials in catalysis
2.1 Metal core@metal shell nanomaterials
2.2 Metal core@oxide shell nanomaterials
2.3 Metal core@carbon shell nanomaterials
2.4 Metal core@polymer shell nanomaterials
2.5 Metal core@zeolite shell nanomaterials
2.6 Yolk/shell structure nanomaterials