The recent insights into inorganic-organic material advancements for the development of flexible thermoelectric devices: A review

Increasing concern over fossil fuel depletion and environmental sustainability has led to the emergence of thermoelectric (TE) technology as a promising green energy solution for converting waste heat into electricity. Organic–inorganic hybrid materials have recently gained attention due to their potential to synergistically combine the low thermal conductivity of organic components with the high Seebeck coefficient and electrical conductivity of inorganic components. These hybrid thermoelectric materials combine the superior thermoelectric properties of inorganic compounds with the mechanical flexibility, low cost, and facile processability of organic materials. These hybrids are well-suited for harvesting low-grade waste heat from sources such as industrial systems and human bodies. This review discusses interfacial engineering and dimensional design strategies for enhancing TE performance in such hybrid systems. It also focuses on the emerging class of flexible thermoelectric materials, which hold immense promise for powering next-generation wearable and portable electronics. We discuss recent progress in materials design, with particular emphasis on strategies such as band structure engineering, interfacial engineering, and nanostructuring to optimize electrical transport and power factor while suppressing thermal conductivity. It also covers advances in fabrication techniques for flexible thermoelectric generators (f-TEGs), addressing both performance optimization and mechanical adaptability.