Pinhole-free ionic conductors are critical to achieve optimal performance in thin film-solid oxide fuel cells (TF-SOFCs). However, nanoscale defects, especially pinholes, can induce current leakage and contribute to cell failure by creating electrical short circuits. This study introduced a novel methodology for detecting pinholes in yttria-stabilized zirconia (YSZ) thin-film solid oxide electrolytes. The approach utilized selective adsorption of silver (Ag) nanoparticles generated via a spark discharge generator (SDG). Analytical techniques, including focused ion beam (FIB), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were employed to investigate interactions between Ag nanoparticles and nanoscale defects. Results showed that nanoparticle-based diagnostic methods were efficacious for defect characterization, offering a solution for enhancing the quality of thin-film electrolytes.

Recent developments in additive manufacturing (AM) process have led us to fabricate many mechanical and electrical components or devices into complex geometries. Within existing AM processes, laser is widely used as an energy source to selectively sinter particles with a powder bed fusion (PBF) process or cure photopolymers with a vat photopolymerization (VPP) process. This study investigated the applicability of the SLS process for silver nanoparticles (Ag NPs)-photopolymer inks to fabricate micro-scale conductive patterns. With Ag NPs-photopolymer inks prepared with different mixture ratios and pasted on a polyethylene terephthalate (PET) substrate, a pulse width modulation (PWM) signal-controlled 405 nm laser was applied to these inks to selectively sinter and cure the Ag NPs and the photopolymer simultaneously. The final conductive patterns were obtained after a rinse in ethanol to remove un-sintered and un-cured regions of the inks. Microstructures, thickness profiles, pattern width, electrical resistance, and resistivity of the fabricated patterns were investigated by varying the PWM duty and the laser exposure time. Effects of different numbers of scan lines in the pattern and nanoparticle mixture ratios were also investigated. The proposed method is cost effective and easy with fast patterning capabilities. It will leverage practical advances in AM industries.