Mass Diffusion Metamaterials with “Plug and Switch” Modules for Ion Cloaking, Concentrating, and Selection: Design and Experiments

Abstract

The outstanding abilities of metamaterials to manipulate physical fields are extensively studied in both wave-based and diffusion-based fields. However, mass diffusion metamaterials, with the ability to manipulate diffusion with practical applications associated with chemical and biochemical engineering,have not yet been experimentally demonstrated. In this work, ion cloaking, concentrating, and selection in liquid solvents are verified by both simulations and experiments, and the concept of a "plug and switch" metamaterial is proposed based on scattering cancellation (SC) to achieve switchable functions by plugging modularized functional units into a functional motherboard. Plugging in any module barely affects the environmental diffusion field, but the module choice impacts different diffusion behaviors in the central region. Cloaking strictly hinds ion diffusion, and concentrating increase diffusion flux, while cytomembrane-like ion selection permits the entrance of some ions but blocks others. In addition, these functions are demonstrated in special applications like the catalytic enhancement by the concentrator and the protein protection by the ion selector. This work not only experimentally demonstrates the effective manipulation of mass diffusion by metamaterials, but also shows that the "plug and switch" design is extensible and reconfigurable. It facilitates novel applications including sustained drug release, catalytic enhancement, bioinspired cytomembranes, etc.

Design via topology optimisation and experimental assessment of thermal metadevices for conductive heat flux shielding in transient regime

“…Nowadays, the increasing development of metamaterials and metadevices (devices made of metamaterials or that macroscopically behave as such) allows the manipulation of several physical fields in extreme and unprecedented ways. Such an outstanding potential of both metamaterials and metadevices has found noteworthy applications in optics and electromagnetism [1] , sounds and vibrations [2,3] , heat transfer [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] , mass transfer [22][23][24][25] , mechanics [26][27][28] and thermomechanics [29][30][31] . Most of the metamaterials conceived for the aforementioned applications have been designed using the standard coordinates transformation approach originally introduced by Leonhardt [32] and Pendry [33] in the context of electromagnetism, whose particular implementation in the search for invariant forms of the heat conduction equation for several conductive heat flux manipulation purposes has given rise to the concept of transformation thermodynamics (TT) [18,34,35] .…”