Atomic Tuning in Electrically Conducting Bimetallic Organic Frameworks for Controllable Electromagnetic Wave Absorption
Congjie Chen, Zhen Shan, Shifei Tao, Aming Xie, Hongwei Yang, Jian Su, Satoshi Horke, Susumu Kitagawa, Gen Zhang
Abstract
Abstract Due to the structural complexity and limited controllability of conventional microwave‐absorption materials (MAMs), the precise regulation of atomically‐resolved structures and properties of MAMs remains a significant challenge. The interpretation of the dielectric loss mechanism is usually conduction and polarization losses, while the absence of components‐regulated template materials further hinders the disclosure of the mechanism. Herein, based on the customizable functionality of the MOF platform, a series of pristine bimetallic MOFs with precise and controllable conductivity are successfully constructed through the bimetallic alloying strategy. The controllability is attributed to the alteration of free‐carrier concentration and the subtle difference of interlayer displacement or spacing, both of which originate from the atomic tuning of hetero‐metal. Notably, Cu 1.3 Ni 1.7 (HITP) 2 features an ultra‐high absorption strength (reflection loss, RL = −71.5 dB) and an ultra‐wide maximum bandwidth (6.16 GHz) at only 15% filling, which ranked in the upper range of all reported MAMs. Due to the metal co‐synergies, Cu 1.3 Ni 1.7 (HITP) 2 possesses a switchable high absorption peak in a wide range (4–18 GHz). This work opens up an avenue for tailoring the atomic tuning of new MOF‐based electromagnetic wave absorbers and provides a conceptually novel platform.