Ashish Ghimire

This study presents a novel hierarchical nested honeycomb drawing inspiration from the hierarchical structures found in energy-absorbing citrus peels. Our investigation reveals that integrating secondary hierarchical units into primary honeycomb cells results in energy absorption profiles featuring two distinct plateaus. Notably, we found that these profiles can be finely tuned by adjusting the thickness of primary and secondary cell walls. Additionally, our study demonstrates a strategic removal of cell walls at key positions, reducing material consumption without compromising specific energy absorption. By establishing comprehensive structure–property relationships, we offer valuable insights into the design and optimization of hierarchical cellular materials. Compared with traditional honeycomb structures, the nested honeycomb structure shows a twofold increase in compressive strength and a fivefold increase in specific energy absorption, positioning them as promising candidates for applications requiring two-step impact protection and tunable performance, ranging from packaging to high-speed automobiles.

The energy crisis of the 1970s sparked growing concern over minimizing fuel consumption in water, land, and air transportation. Researchers fascinated by sharks' effortless swimming abilities investigated shark skin denticles and uncovered functions beyond drag reduction, such as antifouling, protection, and bioluminescence. Over the past five decades, significant progress has been made in comprehending drag reduction and antifouling functions of denticle structures; however, the investigation of other functions remains limited. Recent discoveries of diverse denticle morphologies have ignited a keen interest in obtaining morphogroups that can aid other functional studies. This work integrates advances in antifouling, hydrodynamics, aerodynamics, bioluminescence, and protective functions to provide a holistic understanding of their diverse roles. Additionally, this work also dictates multi‐functional adaptations of denticles and contributes to the relatively less‐explored but essential aspects, such as protective functions and denticle morphogroups. By examining these functions together, this work aims to uncover potential synergies and interactions, facilitating the development of multifunctional materials inspired by shark skin denticles.