Expandable Microspheres Transform 2D Electrospun Mats Into 3D Composite Scaffolds

Electrospun nanofibers have proven versatile across numerous fields, including environmental, energy, and biomedical applications. Typically, however, electrospun nanofiber materials are fabricated as two-dimensional sheets, membranes, or mats. In this study, a straightforward and adaptable foaming method is presented to create three-dimensional microsphere-nanofiber composite structures. This approach involves incorporating expandable microspheres within the nanofiber mats during electrospinning, followed by thermal treatment to achieve the 3D morphology. The expansion ratio and compressive strength increase with higher concentrations of expandable microspheres. In addition, the compressive strength of the 3D composite structures significantly surpasses that of 3D nanofiber scaffolds expanded with subcritical CO₂ fluids. This approach presents a promising pathway for fabricating 3D microsphere-nanofiber composite scaffolds with broad potential applications.