Siddique, Suhail K.Suhail K.SiddiqueSadek, HassanHassanSadekWang, Chi WeiChi WeiWangLee, Chang ChunChang ChunLeeTsai, Cheng YuanCheng YuanTsaiChang, Shou YiShou YiChangLi, Chia LinChia LinLiCHUN-HWAY HSUEHHo, Rong MingRong MingHo2023-07-242023-07-242023-12-0118844049https://scholars.lib.ntu.edu.tw/handle/123456789/634101Herein, this work aims to develop a facile method for the fabrication of metallic mechanical metamaterial with a well-ordered diamond structure from a bottom-up approach using a self-assembled block copolymer for templated electrochemical deposition. By controlling the effective volume fraction of PDMS in PS-b-PDMS via solvent annealing followed by HF etching of PDMS, it is feasible to obtain nanoporous PS with diamond-structured nanochannels and used it as a template for templated electrochemical deposition. Subsequently, well-ordered nanonetwork gold (Au) can be fabricated. As evidenced by nanoindentation and micro-compression tests, the mechanical properties of the diamond-structured Au after removal of PS give the combination of lightweight and mechanically robust characteristics with an exceptionally high reduced elastic modulus of 11.9 ± 0.6 GPa and yield strength of 193 ± 11 MPa above the Hashin-Shtrikman upper bound of 72 MPa with a bending-dominated structure at equivalent density. The corresponding deformation mechanism can be elucidated by morphological observations experimentally and finite element analysis (FEA) numerically. This work demonstrates the bottom-up approach to fabricating metallic monolith with diamond structure in the nanoscale, giving a superior performance as mechanical metamaterials.journal article10.1038/s41427-023-00483-y2-s2.0-85162878437https://api.elsevier.com/content/abstract/scopus_id/85162878437