Cordonier G Jacob, Anderson Kyleigh, Butts Ronan, O'Hara Ross, Garneau Renee, Wimer Nathanael, Kuhlman John M, Sierros Konstantinos A
Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, West Virginia 26506, United States.
ACS Appl Mater Interfaces. 2023 Oct 11;15(40):47745-47753. doi: 10.1021/acsami.3c09658. Epub 2023 Sep 28.
This work explores the potential for additive manufacturing to be used to fabricate ultraviolet light-blocking or photocatalytic materials with in situ resource utilization, using a titania foam as a model system. Direct foam writing was used to deposit titania-based foam lines in microgravity using parabolic flight. The wet foam was based on titania primary particles and a titania precursor (Ti (IV) bis(ammonium lactato) dihydroxide). Lines were also printed in Earth gravity and their resulting properties were compared with regard to average cross-sectional area, height, and width. The cross-sectional height was found to be higher when printing at low speeds in microgravity compared to Earth gravity, but lower when printing at high speeds in microgravity compared to Earth gravity. It was also observed that volumetric flow rate was generally higher when writing in Earth gravity compared to microgravity. Additionally, heterogeneous photocatalytic degradation of methylene blue was studied to characterize the foams for water purification and was found to generally increase as the foam heat treatment temperature increased. Optical and scanning electron microscopies were used to observe foam morphology. X-ray diffraction spectroscopy was used to study the change in crystallinity with respect to temperature. Contact angle of water was found to increase on the surface of the foam as ultraviolet light exposure time increased. Additionally, the foam blocked more ultraviolet light over time when exposed to ultraviolet radiation. Finally, bubble coarsening measurements were taken to observe bubble radius growth over time.
这项工作以二氧化钛泡沫为模型系统，探索了增材制造用于原位资源利用来制造紫外线阻挡或光催化材料的潜力。利用抛物线飞行，采用直接泡沫书写法在微重力环境下沉积基于二氧化钛的泡沫线。湿泡沫基于二氧化钛初级颗粒和二氧化钛前驱体（二羟基双（乳酸铵）钛（IV））。还在地球重力环境下打印线条，并将其所得性能在平均横截面积、高度和宽度方面进行比较。结果发现，与地球重力环境下相比，在微重力环境下低速打印时横截面高度更高，但在微重力环境下高速打印时与地球重力环境下相比更低。还观察到，与微重力环境下相比，在地球重力环境下书写时体积流速通常更高。此外，研究了亚甲基蓝的非均相光催化降解以表征用于水净化的泡沫，发现其通常随着泡沫热处理温度的升高而增加。使用光学显微镜和扫描电子显微镜观察泡沫形态。利用X射线衍射光谱研究结晶度随温度的变化。发现随着紫外线照射时间的增加，泡沫表面水的接触角增大。此外，泡沫在暴露于紫外线辐射时，随着时间的推移阻挡了更多的紫外线。最后，进行气泡粗化测量以观察气泡半径随时间的增长情况。
