Four-Dimensional Micro/Nanorobots via Laser Photochemical Synthesis towards the Molecular Scale

Abstract

Miniaturized four-dimensional (4D) micro/nanorobots denote a forerunning technique associated with interdisciplinary applications, such as in embeddable labs-on-chip, metamaterials, tissue engineering, cell manipulation, and tiny robotics. With emerging smart interactive materials, static micro/nanoscale architectures have upgraded to the fourth dimension, evincing time-dependent shape/property mutation. Molecular-level 4D robotics promises complex sensing, self-adaption, transformation, and responsiveness to stimuli for highly valued functionalities. To precisely control 4D behaviors, current-laser-induced photochemical additive manufacturing, such as digital light projection, stereolithography, and two-photon polymerization, is pursuing high-freeform shape-reconfigurable capacities and high-resolution spatiotemporal programming strategies, which challenge multi-field sciences while offering new opportunities. Herein, this review summarizes the recent development of micro/nano 4D laser photochemical manufacturing, incorporating active materials and shape-programming strategies to provide an envisioning of these miniaturized 4D micro/nanorobots. A comparison with other chemical/physical fabricated micro/nanorobots further explains the advantages and potential usage of laser-synthesized micro/nanorobots.

Editorial for the Special Issue on Laser Additive Manufacturing: Design, Materials, Processes, and Applications, 2nd Edition

“…This Special Issue covers a wide range of forming materials, including zirconium alloys [ 24 ], titanium alloys [ 20 , 23 ], steel [ 21 , 25 , 26 ], composites (e.g., electroless copper and carbon fiber [ 27 ]), and in particular, metallic multi-materials (e.g., copper/silver [ 22 ]), 4D printing materials (e.g., NiTi, smart materials for soft interactive hydrogel [ 19 ]).…”

“…This Special Issue focuses on macro-advanced manufacturing (e.g., laser powder bed fusion (L-PBF) [ 18 ], wire arc additive manufacturing (WAAM) [ 21 ]), but also on micro-advanced manufacturing (e.g., laser photochemical synthesis [ 19 ]). Furthermore, the process optimizations on the adhesion strength [ 28 ] and the mechanical properties [ 24 ] (in-process) and the influence of aging treatment regimens on the microstructure and mechanical properties [ 25 ] (post-process) were investigated.…”

“…The findings of this Special Issue are expected to provide guidance and reference for scientists and engineers in the fields of aerospace (e.g., space camera and aircraft landing gear [ 23 ]), energy (e.g., fuel envelope positioning lattices of pressurized water reactors, component boxes, and heat exchangers [ 24 ]), and micromachines (e.g., four-dimensional microrobots/nanorobots [ 19 ]).…”

“…As depicted in Figure 1 , this Special Issue featured a diverse array of topics, publishing a total of 11 contributions, comprising 10 original research articles and 1 review paper. After the high-quality reviewing process, four articles [ 18 , 19 , 20 , 21 ] were selected as Editor’s Choice. Each of them is briefly introduced below according to four aspects (i.e., design, materials, processes, and applications) of the laser additive manufacturing in this Special Issue.…”

The Influence of Laser Process Parameters on the Adhesion Strength between Electroless Copper and Carbon Fiber Composites Determined Using Response Surface Methodology

“…In comparison, laser process technology offers numerous many advantages, including noncontact operation, high precision, region selection, controllability, simplicity, and applicability to a wide range of materials [15][16][17][18][19], which make it a promising method for preparing metal-coated CFCs with high adhesion. For instance, Gustke et al proposed a pulsed laser roughening method for enhancing the adhesion strength between a sprayed copper layer and CFCs.…”