Chinn Alexandra C, Marsh Eric L, Nguyen Tim, Alhejaj Zackarea B, Butler Matthew J, Nguyen Bachtri T, Sasan Koroush, Dylla-Spears Rebecca J, Destino Joel F
Department of Chemistry & Biochemistry, Creighton University, 2500 California Plaza, Omaha, Nebraska 68178, United States.
Omaha North High Magnet School, 4410 N 36th Street, Omaha, Nebraska 68111, United States.
ACS Omega. 2022 May 10;7(20):17492-17500. doi: 10.1021/acsomega.2c02292. eCollection 2022 May 24.
Core-shell colloids make attractive feedstocks for three-dimensional (3D) printing mixed oxide glass materials because they enable synthetic control of precursor dimensions and compositions, improving glass fabrication precision. Toward that end, we report the design and use of core-shell germania-silica (GeO-SiO) colloids and their use as precursors to fabricate GeO-SiO glass monoliths by direct ink write (DIW) 3D printing. By this method, GeO colloids were prepared in solution using sol-gel chemistry and formed oblong, raspberry-like agglomerates with ∼15 nm diameter primary particles that were predominantly amorphous but contained polycrystalline domains. An ∼15 nm encapsulating SiO shell layer was formed directly on the GeO core agglomerates to form core-shell GeO-SiO colloids. For glass 3D printing, GeO-SiO colloidal sols were formulated into a viscous ink by solvent exchange, printed into monoliths by DIW additive manufacturing, and sintered to transparent glasses. Characterization of the glass components demonstrates that the core-shell GeO-SiO presents a feasible route to prepare quality, optically transparent low wt % GeO-SiO glasses by DIW printing. Additionally, the results offer a novel, hybrid colloid approach to fabricating 3D-printed Ge-doped silica glass.
核壳胶体是用于三维（3D）打印混合氧化物玻璃材料的有吸引力的原料，因为它们能够对前驱体的尺寸和组成进行合成控制，从而提高玻璃制造精度。为此，我们报告了核壳氧化锗-二氧化硅（GeO-SiO）胶体的设计和使用，以及它们作为前驱体通过直接墨水书写（DIW）3D打印来制造GeO-SiO玻璃整体材料的用途。通过这种方法，使用溶胶-凝胶化学在溶液中制备了GeO胶体，并形成了椭圆形、覆盆子状的团聚体，其初级颗粒直径约为15 nm，主要为非晶态，但含有多晶域。在GeO核团聚体上直接形成了一个约15 nm的封装SiO壳层，以形成核壳GeO-SiO胶体。对于玻璃3D打印，通过溶剂交换将GeO-SiO胶体溶胶配制成粘性墨水，通过DIW增材制造打印成整体材料，然后烧结成透明玻璃。对玻璃成分的表征表明，核壳GeO-SiO为通过DIW打印制备高质量、光学透明的低重量百分比GeO-SiO玻璃提供了一条可行的途径。此外，这些结果为制造3D打印的掺Ge二氧化硅玻璃提供了一种新颖的混合胶体方法。
