Nondestructive Approach for Additive Nanomanufacturing of Metallic Nanostructures in the Air

Abstract

In this article, a mechanism for quick release and transfer of gold nanoparticles (GNPs) from a soft substrate to another substrate under laser illumination is investigated. The heating of GNPs on a soft substrate with a continuous-wave laser causes a rapid thermal expansion of the substrate, which can be used to selectively release and place GNPs onto another surface. In-plane and out-of-plane nanostructures are successfully fabricated using this method. This rapid release-and-place process can be used for additive nonmanufacturing of metallic nanostructures under ambient conditions, which paves a way for affordable nanomanufacturing and enables a wide variety of applications in nanophotonics, ultrasensitive sensing, and nonlinear plasmonics.

Optical manipulation and assembly of micro/nanoscale objects on solid substrates

“…Alam et al. reported opto-thermomechanical nanoprinting of nanoparticles with nanoscale accuracy operated between two solid substrates ( Alam et al., 2020 ; Alam and Zhao, 2018 ). The target nanoparticles were placed on a donor substrate with a large thermal expansion coefficient, such as polydimethylsiloxane (PDMS).…”

Optical Nanoprinting of Colloidal Particles and Functional Structures

“…Another example of opto-thermomechanical approaches is to release nanoparticles from a donor substrate externally. For instance, Zhao and co-workers reported a release-and-place strategy to fabricate metallic nanostructures in air . A laser is directed to AuNPs that are placed onto a soft plastic donor substrate.…”

“…So far, optical nanoprinting has proved powerful for the construction of 2D nanostructures. Although construction of 3D assemblies was demonstrated, , the number of particles in the 3D nanostructures and their configurations are still limited. This limitation can be potentially addressed by using optical fibers to achieve 3D printing via control over the focus along the z -axis.…”

“…For instance, Zhao and co-workers reported a release-and-place strategy to fabricate metallic nanostructures in air. 95 A laser is directed to AuNPs that are placed onto a soft plastic donor substrate. The plasmon-enhanced heating of AuNPs leads to rapid expansion of the soft substrate, which results in the transfer of AuNPs to another receiver substrate (Figure 6D).…”

Additive Opto-Thermomechanical Nanoprinting and Nanorepairing under Ambient Conditions

“…For example, microsized metallic particles can be selectively melted or sintered by a high-power laser beam to form complex 3D metal parts. − However, it is challenging to directly downsize the existing macro- and microscale 3D printing techniques for nanoscale printing or nanoprinting . Nanoparticles are ideal for serving as the raw materials for nanoprinting either in a liquid or a gaseous environment − due to their custom-designed large-volume and low-cost production with unique physical and chemical properties. , Nanoparticles can be attached to each other through electrostatic or van der Waals forces once they are in contact with each other. Therefore, 3D nanoprinting at the nanoscales can be realized by precisely manipulating and assembling individual nanoparticles to form the final structures.…”