Interface-Engineered HMS/PANI Thermoelectric Device for 3D Printer Waste Heat Harvesting

Abstract

The development of flexible, high-performance thermoelectric materials is necessary due to the growing demand for sustainable energy conversion from waste heat sources. In this work, we present higher manganese silicide/polyaniline (HMS/PANI) composite thin films that exhibit a hierarchical interface design, which partially decouples the typical interrelated thermoelectric parameters for the waste heat recovery of working 3D printers. Structural characterizations - XRD and SEM confirm the well-dispersed HMS network with good interfacial quality. Through systematic composition optimization, we achieved enhanced electrical conductivity, 438 S/m, and a simultaneous increase in Seebeck coefficient of 72 μV/K for 80% HMS content. This enhancement results from hierarchical composite engineering, achieved by percolation-driven charge transfer at HMS/PANI interfaces and energy filtering effects, which also increase carrier concentration. The optimized composition exhibits an enhanced power factor of 2.3 μW/(mK²). The phonon engineering suppresses the lattice thermal conductivity over pure PANI by maximizing the thermoelectric performance of composites. I-V characterization confirms the ohmic transport behaviour across all compositions. Device output characterization demonstrates maximum power generation of 0.33 nW at ΔT = 70 K. Real-time application demonstration on an operating 3D printer reveals stable performance, by generating 6-8 mV output, validating functionality for autonomous IoT energy harvesting systems. This work establishes HMS/PANI composites as a flexible thermoelectric material where sophisticated composite design transcends individual phase limitations, paving the way for practical thermoelectric energy harvesting from diverse waste heat sources.