Freely Suspended Layer-by-Layer Nanomembranes: Testing Micromechanical Properties

Abstract

Freely suspended nanocomposite layer‐by‐layer (LbL) nanomembranes composed of a central layer of gold nanoparticles sandwiched between polyelectrolyte multilayers are fabricated via spin‐assisted LbL assembly. The diameter of the circular membranes is varied from 150 to 600 μm and the thickness is kept within the range of 25–70 nm. The micro‐ and nanomechanical properties of these membranes are studied using a combination of resonance‐frequency and bulging tests, and point‐load nanodeflection experiments. Our results suggest that these freely suspended nanomembranes, with a Young's modulus of 5–10 GPa are very robust and can sustain multiple significant deformations. They are very sensitive to minor variations in pressure, surpassing ordinary semiconductor and metal membranes by three to four orders of magnitude and therefore have potential applications as pressure and acoustic microsensors.

Asymmetric Free-Standing Film with Multifunctional Anti-Bacterial and Self-Cleaning Properties

“…1 Thin free-standing films have aroused great interest because they exhibit dramatically different behavior when compared to bulk materials, with changes in properties such as glass transition, 2-4 transport, [5][6][7] and stress to failure. 8,9 Meanwhile, free-standing films have found great potential use as sensors, 10,11 barrier materials, 12 reflectors, 13 and electronic films. 14,15 Due to their unique properties including high flexibility, non-covalent adhesiveness, transparency and large aspect ratio, free-standing films have found new use in the biomedical field.…”

Development of Fabrication of Giant Nanomembranes

“…29 Tsukruk and co-workers have discussed the mechanical properties of free-standing nanomembrane composites. [30][31][32][33][34][35] Very recently, Ono and Decher have obtained a free-standing polyelectrolyte multilayer with a few centimeter square size by using a suitable sacrificial layer. 36 The thickness of this film is estimated roughly to be 250 nm from the reported number of the deposition cycle.…”

Mechanical properties of nanotubes of polyelectrolyte multilayers

“…The mechanical properties of standard LbL multilayers have been studied for quite some time (Table 1) [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. In the dry state, Young moduli in the 1-13 GPa range were reported for various systems using a variety of testing methods, typical moduli being about 5 GPa for purely organic assemblies, and rising to about 10 GPa upon addition of inorganic components.…”