Our article in PNAS: Crack engineering as a new route for the construction of arbitrary hierarchical
First-ever method to mass-produce 3D hierarchical and biomimetic structures in desired materials Three-dimensional (3D) hierarchical structures are the fundamental elements of numerous biological surfaces that exhibit various fascinating functionalities useful for liquid and mass transport, energy conversion, signal transformation, and topological interaction, etc. In recent years, extensive efforts have been directed towards mimicking these natural inspirations for practical