Aerogels are highly porous structures produced by replacing the liquid solvent of a gel with air without causing a collapse in the solid network. Unlike conventional fabrication methods, additive manufacturing (AM) has been applied to fabricate 3D aerogels with customized geometries specific to their applications, designed pore morphologies, multimaterial structures, etc. To date, three major AM technologies (extrusion, inkjet, and stereolithography) followed by a drying process have been proposed to additively manufacture 3D functional aerogels. 3D‐printed aerogels and porous scaffolds showed great promise for a variety of applications, including tissue engineering, electrochemical energy storage, controlled drug delivery, sensing, and soft robotics. In this review, the details of steps included in the AM of aerogels and porous scaffolds are discussed, and a general frame is provided for AM of those. Then, the different postprinting processes are addressed to achieve the porosity (after drying); and mechanical strength, functionality, or both (after postdrying thermal or chemical treatments) are provided. Furthermore, the applications of the 3D‐printed aerogels/porous scaffolds made from a variety of materials are also highlighted. The review is concluded with the current challenges and an outlook for the next generation of 3D‐printed aerogels and porous scaffolds.
Aerogels are considered ideal candidates for various applications, because of their low bulk density, highly porous nature, and functional performance. However, the time intensive nature of the complex fabrication process limits their potential application in various fields. Recently, incorporation of a fibrous network has resulted in production of aerogels with improved properties and functionalities. A facile approach is presented to fabricate hybrid sol–gel electrospun silica‐cellulose diacetate (CDA)‐based nanofibers to generate thermally and mechanically stable nanofiber aerogels. Thermal treatment results in gluing the silica‐CDA network strongly together thereby enhancing aerogel mechanical stability and hydrophobicity without compromising their highly porous nature (>98%) and low bulk density (≈10 mg cm−3). X‐ray photoelectron spectroscopy and in situ Fourier‐transform infrared studies demonstrate the development of strong bonds between silica and the CDA network, which result in the fabrication of cross‐linked structure responsible for their mechanical and thermal robustness and enhanced affinity for oils. Superhydrophobic nature and high oleophilicity of the hybrid aerogels enable them to be ideal candidates for oil spill cleaning, while their flame retardancy and low thermal conductivity can be explored in various applications requiring stability at high temperatures.
more » « less- NSF-PAR ID:
- 10458876
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 30
- Issue:
- 5
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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