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Abstract 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.
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Sol-gel technologies for additive manufacturing glass materials
Abstract The sol-gel method has shown immense potential in materials science and nanotechnology. One of the cornerstone applications of the sol-gel technique includes the fabrication of inorganic glasses and glass-ceramics at relatively low temperatures as an alternative to conventional high-temperature melt-quench techniques. In recent times, glass fabrication with the sol-gel method has extended to additive manufacturing (AM), also referred to as 3D printing. Current sol-gel, glass AM uses solution-based gel compositions to produce three-dimensional glasses through layer-by-layer deposition and/or using photocurable polymer resins. Owing to its significant advantages of being able to fabricate glass components with arbitrary and complex geometry, AM presents a tantalizing opportunity to fabricate functionalized glass materials, increasing the technique’s popularity over the past decade. In this review and perspective, recent progress in combining sol-gel synthesis and additive manufacturing technologies used for obtaining inorganic glasses are discussed, specifically highlighting the research carried out in North America, and a prospectus of the field and emerging areas of interest and need is presented. Graphical Abstract
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- Award ID(s):
- 2144453
- PAR ID:
- 10567022
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Sol-Gel Science and Technology
- Volume:
- 116
- Issue:
- 3
- ISSN:
- 0928-0707
- Format(s):
- Medium: X Size: p. 2257-2271
- Size(s):
- p. 2257-2271
- Sponsoring Org:
- National Science Foundation
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