3D printing of nanowrinkled architectures via laser direct assembly

Abstract

Structural wrinkles in nature have been widely imitated to enhance the surface functionalities of objects, especially three-dimensional (3D) architectured wrinkles, holding promise for emerging applications in mechanical, electrical, and biological processes. However, the fabrication of user-defined 3D nanowrinkled architectures is a long-pending challenge. Here, we propose a bottom-up laser direct assembly strategy to fabricate multidimensional nanowrinkled architectures in a single-material one-step process. Through the introduction of laser-induced thermal transition into a 3D nanoprinting process for leading the point-by-point nanoscale wrinkling and the self-organization of wrinkle structures, we have demonstrated the program-controlled and on-demand fabrication of multidimensional nanowrinkled structures. Moreover, the precise control of wrinkle morphology with an optimal wavelength of 40 nanometers and the regulation of the dynamic transformation of wrinkled cellular microstructures via interfacial stress mismatch engineering have been achieved. This study provides a universal protocol for constructing nearly arbitrary nanowrinkled architectures and facilitates a new paradigm in nanostructure manufacturing.

Leveraging Microgels Prepared from Poly(ethylene glycol) Bisepoxide and Polyetheramine for Versatile Surface Structuring of Agarose Hydrogels

“…To tune the long-range order of the induced surface patterns in swollen gels, Yang and co-workers harnessed instabilities of glass (or silicon wafer) substrate-bound poly­(hydroxyethyl methacrylate) (PHEMA) hydrogels with the depth-wise cross-linking density gradient . Recently, 3D objects with swelling-induced nanowrinkle morphology were achieved on glass-supported, 3D-printed hydrogels derived from poly­(ethylene glycol) diacrylate and N -isopropylacrylamide . Swollen hydrogels wrinkling was mostly achieved with geometrically constrained hydrogels, where the samples were either placed in containers , or laterally confined by stiff supports such as glass slides. , In contrast, our microgel-on-macrogel system could swell and develop wrinkles without any physical constraint, making it more applicable for future use, where a freestanding form is preferred.…”

Ultrafast laser induced surface instability for 3D nanoprinting wrinkled architectures

“…Consequently, voxels undergoing photopolymerization at a slightly elevated temperature exhibit a swelling phenomenon upon the cessation of laser irradiation. This phenomenon is ascribed to the temperaturetriggered transition in volume phases 1 (Fig. 1c).…”

Femtosecond Laser 4D Printing of Light‐Driven Intelligent Micromachines

“…The homogeneous doping of single-walled carbon nanotubes (SWNTs) inside NIPAM simultaneously increases the light absorption coefficient, thermal conductivity, and mechanical modulus of the crosslinked network of the composite hydrogel, hence resolving the dilemma of the well-known material trade-off between the mechanical modulus and the response sensitivity of stimuli-responsive hydrogels (Figure 1b). Moreover, we designed and assembled different micromachines composed of micromechanical metamaterial units, and realized one-stepone-parameter femtosecond laser direct writing [39][40][41][42][43][44] (FsLDW) processing. In this way, metamaterial unit cells were assembled to achieve heterogeneous gelation with a rigid outer frame and a weak cross-linked soft inner based on proximity effect [43] in FsLDW (Figure 1c,d).…”