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Piezoelectric polymer nanofibers are promising for wearable electronics due to their mechanical compliance and electromechanical responsiveness. Poly(vinylidene fluoride)‐trifluoroethylene (PVDF‐TrFE) is widely used for its ferroelectric β ‐phase and favorable piezoelectric properties, yet its limited elasticity hinders applications in soft bioelectronics. Electrospun PVDF‐TrFE mats can stretch through fiber rearrangement but lack true elastic recovery unless molecular interactions and junctions are modified. Achieving nanofiber networks that are both stretchable and piezoelectrically stable under cyclic strain remains a challenge. Here, we report a strategy combining PVDF‐TrFE with a small fraction of poly(ethylene glycol) bis(amine) (PEG‐diamine) and thermal annealing to form fused nanofibrous mats with enhanced elasticity and stable piezoelectric output. The blended mats doubled the strain‐to‐failure (~30%) compared to pure PVDF‐TrFE (~14%) and showed Mullins‐like elastic recovery up to approximately 9% with reduced hysteresis. Piezoelectric response improved by approximately 25% in peak voltage (~150 mV), with greater signal stability. Structural analyses (Fourier‐transform infrared [FTIR], differential scanning calorimetry [DSC], and X‐ray diffraction [XRD]) confirmed increased β ‐phase content and selective cross‐linking in amorphous domains without compromising ferroelectric order. This work demonstrates a scalable material‐based approach to improve elasticity and durability in electrospun piezoelectric fibers, enabling stretchable and skin‐conformable sensors for smart fabrics, wearable health monitors, and energy harvesting.

Additive manufacturing, particularly vat photopolymerization (VPP) 3D printing has emerged as a promising method for manufacturing advanced ceramics and metal-ceramic composites with tailored porosity, microstructure, and mechanical properties. This dissertation investigates the development of porous Yttria-Stabilized Zirconia (YSZ) ceramics and copper-alumina (Cu/Al2O3) metal-ceramic composites.Despite their critical roles in energy storage and conversion, filtration, catalytic support, electronics, and biomedical implants, microporous ceramics are predominantly manufactured in simple geometries. Digital Light Processing (DLP) 3D printing offers the capability to produce complex ceramic geometries; however, existing photocurable slurries are primarily designed for dense ceramics. Two approaches were developed to achieve controlled porosity in YSZ ceramics. First, partial sintering was used to obtain porosities between 6% and 40%, with grain sizes ranging from 80 nm to 550 nm. A porosity of ~33% resulted in a Weibull modulus of 5.3 and a flexural strength of over 36 MPa, with thermal shock resistance up to 500°C. Second, a novel a custom-designed zirconia photocurable slurry by particles with low relative roundness (RR ~ 0.37). The low RR of these coarse particles contributed to pore formation in the sintered ceramic body, maintaining porosity. Additionally, by tailoring the different ratios of coarse and fine particles within the custom photocurable ceramic suspension, we were able to control porosity, ranging from 20% to 40%.In addition to porous ceramics, this work introduces a novel hybrid manufacturing approach to fabricate copper-alumina (Cu/Al2O3) metal-ceramic composites by combining vat photopolymerization 3D printing with pulsed electrodeposition (PED). This technique enables efficient metal infiltration into the intricate channels of a 3D-printed ceramic scaffold, resulting in a composite with remarkable mechanical properties. Unlike traditional high-temperature infiltration methods, this process operates at room-temperature, requires no external pressure processing, and reduces energy consumption by over 47-fold. The resulting composite exhibits substantial performance improvements, including a 24-fold increase in strength, and a 64-fold increase in mechanical energy absorption compared to the ceramic preform.