Resistive pressure sensors based on freestanding membranes of gold nanoparticles

Abstract

In this communication the application of gold nanoparticle membranes as ambient pressure sensors with electromechanical signal transduction is demonstrated. The devices were fabricated by sealing microstructured cavities with membranes of 1,6-hexanedithiol cross-linked gold nanoparticles, which were electrically contacted by metal electrodes deposited on both sides of the cavities. Variations of the external pressure resulted in a deflection of the membranes and, thus, increased the average interparticle distances. Therefore, the pressure change could easily be detected by simply monitoring the resistance of the membranes.

Metallic nanoparticle-based strain sensors elaborated by atomic layer deposition

“…At a strain of 0.5%, a sensitivity DR=R e of 70 is reached which is comparable to that of the NP-based strain gauges elaborated from colloidal solutions. 13,14,17,19,20 As previously suggested in the literature, [13][14][15][16][17][18][19][20] the exponential increase of DR/R with tensile strain e which is observed in Fig. 3(b) is consistent with the exponential dependence of tunnelling resistance on the interparticle separation distance.…”

“…1 For the last ten years, the research on piezoresistive transducers has mainly been focused on the use of nanomaterials to optimize sensitivity, power consumption, and sensor miniaturization. For instance, Si nanowires, [2][3][4] carbon nanotubes, [5][6][7] graphene, [8][9][10] MoS 2 , 10 SiC nanoribbons, 11 Ag nanowires, 12 and metallic nanoparticle (NP) assemblies [13][14][15][16][17][18][19][20] have been exploited at the laboratory scale to achieve very large gauge factors (GFs) which rival the state-of-the-art bulk Si gauges. Although the use of nanomaterials has attracted a lot of attention in the literature these past few years, many technological obstacles (manipulation of individual nanostructures, complexity of the process, sensor reproducibility, etc.)…”

“…According to the literature, the high sensitivity of metallic NP strain gauges is attributed to the modulation, with respect to the strain, of electron tunnelling events between neighbouring NPs. [13][14][15][16][17][18][19][20] These metallic NP strain sensors are usually elaborated from colloidal solutions which are transferred to a variety of substrates by inkjet printing, airbrush spraying, layer-by-layer deposition, centrifugal method, or convective self-assembly. [13][14][15][16][18][19][20] However, such processes are unconventional for the silicon industry, and therefore, they cannot address traditional MEMS applications.…”

Freestanding Ultrathin Nanoparticle Membranes Assembled at Transient Liquid–Liquid Interfaces

“…In addition, the absence of a substrate allows mass transport through the assembly, an essential aspect for filtration applications . While lightweight and flexible, these systems possess high robustness, and can reversibly withstand significant deformations, allowing for the realization of accurate mechanical systems . The mechanical properties necessary to achieve a freestanding material can be obtained through covalent bonds, metal coordination as well as noncovalent reticulation or through the coassembly of the NPs with polymers, DNA or peptides …”

Electrostatically Actuated Membranes of Cross-Linked Gold Nanoparticles: Novel Concepts for Electromechanical Gas Sensors

“…For example, their use in medical diagnosis and integration into wearable electronics has been demonstrated [1]. Recently, freestanding GNP-membranes gained considerable attention and current research activities explore their fundamental electromechanical properties as well as their application as actuators and highly sensitive sensors [2][3][4]. In previous works we studied the application of α,ω-alkanedithiol crosslinked GNP-membranes as electrostatically driven actuators [5] and resonators [6].…”