Hollow Cu_xO (x = 2, 1) micro/nanostructures: synthesis, fundamental properties and applications

Hollow micro/nanostructures possess fascinating physicochemical properties that would generate great application potential in the fields of catalysis, sensing and energy conversion. In the past decades, much more efforts have been employed in the exploration and enrichment of copper-based binary oxides, Cu_xO (x = 2, 1); thus a number of Cu_xO micro/nanostructures with well-controlled ingredients and morphologies have been rationally synthesized and applied. However, a thorough summary on hollow Cu_xO materials has been lacking so far and it is urgently necessary to further promote the progress in novel function-directed Cu_xO-based micro/nanostructures. In this review, we will comprehensively summarize the important advances in hollow Cu_xO micro/nanostructures with tailored morphologies, including the universal synthesis strategies and formation mechanisms, the interfacial Cu–O atomic structures as well as the intrinsic properties, and their potential applications. Remarks on emerging issues and promising research directions are also discussed.