Advanced Bi2Te3/BiSbTe3 segmented thermoelectric panels for rooftop sustainability and exhaust heat management: An integrated DFT and finite element simulation approach

Thermoelectric generators (TEGs) serve as a dual-edged sword in the journey towards minimizing heat pollution and advancing sustainable green energy solutions, adoptable to energy-efficient buildings. Especially, hybrid solar photovoltaics integrated with adaptive TEG panels can use the excess heat developed in the modules owing to the infrared component of solar radiation. The present study investigates the performance optimization of cutting-edge segmented thermoelectric generators (STEGs) using bismuth telluride (Bi 2 Te 3 ) and bismuth-antimony telluride (BiSbTe 3 ) as the thermoelectric materials against the respective hot and cold ends. Density functional theory (DFT) is utilized to examine the electronic, vibrational, thermodynamic, and dielectric properties of these base materials, while finite element simulation (FES) is employed to design efficient device architecture and optimize consolidated thermoelectric performance. Both Bi 2 Te 3 and BiSbTe 3 are found to be dynamically stable, superior electronic conductor owing to nominal band-gap and high static dielectric constants of 24.4 and 35.3, respectively. FES simulations explore scalable STEG configurations with temperature differences Δ T from 27 to 227 K, and varying leg-ratios. The 75 % Bi 2 Te 3 column-length yields optimal performance, with a thermo-emf of 0.101 V and an electric field of 184 mV cm −1 at Δ T = 227 K. Additionally, cost-effective and industry-grade STEG framework is proposed for robust thermoelectric output, exemplified by a 10 × 10 array yielding as high as 76.10 V, compared to 0.101 V from a single unit. These findings highlight the potential of large-scale, compact and durable STEG assembly in enhancing energy conversion efficiency across a wide range of temperature gradients, making them viable for diverse applications. • STEG panels incorporating Bi 2 Te 3 & BiSbTe 3 optimized for high thermoelectric efficiency. • DFT reveals superior electronic, vibrational and dielectric traits of the compounds. • FES maps thermo-emf against temperature gradient for varying configurations and Δ T . • STEG with 75 % Bi 2 Te 3 column-length achieves optimal thermo-emf and electric field. • STEG arrays show high output, up to 76.10 V for 10 × 10 arrays under 227 K difference.