Thermoelectric (TE) technology, capable of converting heat directly into electricity, holds great promise for applications requiring efficient energy output, such as wearable devices and aerospace vehicles. However, the widespread use of traditional TE materials is limited by challenges such as high density, brittleness, and coupling of thermoelectric parameters. Porous TE materials offer a potential solution by enabling lightweight, enhancing mechanical flexibility, and reducing thermal conductivity by rational design and precise control of the pore structure. This review examined recent advances in the construction of optimized pore structures, including the size, distribution, and geometry. We summarized the state-of-the-art synthesis and classification for porous TE materials, highlighting methods for tuning pore configurations to enhance TE efficiency. Additionally, we also collected the cutting-edge device ensemble strategies and demonstrated their application such as aerospace, temperature management, and medical devices. Finally, we took an outlook on the rational and intelligent design of pore structures and their integration into systems for energy output. This review provides new understanding of mechanisms and designs for porous TEs, and also offers valuable guidance for the development of next-generation materials and their application in innovative self-powered systems.

The p-type Te-free Cu₃SbSe₄ with famatinite structure is a potential candidate for thermoelectric materials due to the low cost and eco-friendly constituent elements. However, its strong bipolar effect and high lattice thermal conductivity (κ_lat) are the main challenges for its performance enhancement. Herein, we report a new strategy to enhance its figure of merit zT ~0.86 at 673 K for Cu₃Sb_0.95Fe_0.05Se_2.8S_1.2 via band structure tuning and hierarchical architecture. Firstly, S substituted Se atoms in lattice can widen the band gap to alleviate the bipolar effect. Secondly, Fe doping in Sb site significantly increases the density of states, thus increasing the carrier effective mass, and obtaining a remarkably high Seebeck coefficient of ~560 μV/K at 300 K. Moreover, the induced hierarchical architecture defects resulting in a minimum κ_lat of ~0.48 W·m⁻¹·K⁻¹ at 673 K. Consequently, the improved Seebeck coefficient combined with low thermal conductivity leads to an enhanced zT.