Organic materials hold considerable promise for thermoelectric applications, particularly in flexible devices, due to their pliable and lightweight nature. Recent progress in this domain has been fueled by enhancements in organic thermoelectric materials and more efficient device designs. This review offers a comprehensive overview of these advancements. It begins by detailing the evolution and performance optimization of high-efficiency organic thermoelectric materials, emphasizing both chemical and physical modifications. The review also delves into innovative design strategies for flexible devices, covering new structural approaches, performance modeling, and thermal management techniques. Moreover, it examines advanced manufacturing processes like 3D printing and thin-film deposition. To highlight global trends and challenges, the review integrates findings from top research institutions. The review projects future breakthroughs in material development, characterization techniques, and device optimization, particularly focusing on advances in materials such as PEDOT:PSS and PANI. It underscores strategies to boost conductivity and the Seebeck coefficient. Remarkably, innovative device designs have substantially enhanced energy conversion efficiency, while numerical simulations have improved output voltage and power density. Furthermore, cutting-edge manufacturing technologies like 3D printing and solution processing have facilitated the scalable production of intricate structures. In summary, these collective advancements drive high-performance, cost-effective, and sustainable thermoelectric technologies for diverse applications, including wearable electronics, energy harvesting, and thermal management.
