A series of crumpled ball-like metal oxide-based catalysts enabled by aerosol synthesis.

Two-dimensional nano metal oxides (2D-NMOs) have attracted great concerns due to high exposure of active sites and short ion transport distance. However, 2D-NMOs with the layered structure render to restack into bulk ones, resulting in the active-sites coverage and ion-transport blockage. Here, crumpled 2D NMOs with paper-ball-like shape was proposed to avoid the restacking. Our new strategy can convert diversity of metal oxide into paper-ball-like structure with controllable composition by overcoming the fragile nature of metal oxide and limitation of growth pattern. Resultantly, as-prepared 2D NMOs demonstrated superior catalytic activity and durability in both oxygen evolution reaction (OER) and organic dye degradation reaction, owing to their high exposure of active sites and low ionic diffusion resistance. [Display omitted] • More than 18 crumpled ball-like metal oxide-based catalysts enabled by aerosol synthesis, which was to assemble 2D NMOs into 3D crumpled morphology. • Ultrafine nanocrystals interconnected to form 2D nanosheets in NMOs, endowing more active sites and highly exposed surface. • The crumpled morphology demonstrated superior catalytic activity and durability in both OER and degradation. • Crumpled ball-like metal oxide-based catalysts were assembled by aerosol synthesis, which has more active sites, highly exposed surface and efficient channels. [ABSTRACT FROM AUTHOR]