Multifunctional Screen-Printed Conductive Inks: Design Principles, Performance Challenges, and Application Horizons

This review presents a comprehensive and unified examination of multifunctional screen-printed conductive inks, emphasizing their design principles, rheological behavior, and performance tailored to specific applications. Screen printing, as a scalable and cost-effective technique for printed electronics, demands inks with precisely engineered properties. This work critically analyzes ink formulation strategies across diverse material systems, metallic (e.g., Ag and Cu), carbon-based (graphene and CNTs), polymeric, and hybrid composites, linking their composition (viscosity, yield stress, and thixotropy) to print fidelity and electrical performance. The interplay between rheology, mesh-substrate interactions, stencil dynamics, and wettability is explored to establish structure–property-performance relationships. Particular emphasis is placed on sustainable ink systems, including water-based dispersions, bioderived binders, and environmentally benign solvents. Application domains such as microsupercapacitors, wearable electronics, and biosensors are examined through quantitative metrics like areal capacitance, gauge factor, sensitivity, and long-term stability. The review highlights critical challenges, including achieving nanoscale resolution, ensuring ink-substrate compatibility, and maintaining long-term material stability. By systematically bridging fundamental insights with emerging technologies, this review establishes a benchmark for the rational design of next-generation screen-printable inks, providing a roadmap for both academic research and industrial development in sustainable, high-performance printed electronics.