Controlled Growth of Bronze Telluride for Scalable Thermoelectric Energy Harvesting

TL;DR

This paper presents a scalable, environmentally friendly synthesis of bronze telluride (BT) with enhanced thermoelectric performance, demonstrating its potential for waste heat recovery through experimental and theoretical analysis.

Contribution

It introduces a sustainable CVD-assisted tellurization method for producing high-ZT Cu2Te-based materials and evaluates their practical application in thermoelectric modules.

Findings

BT achieved ZT of 1 at 500 K.

BT generated 2.8 mV across 35 K in a thermoelectric module.

Thermodynamic and DFT studies elucidated formation and behavior mechanisms.

Abstract

With the growing demand for sustainable and decentralized energy solutions, thermoelectric energy harvesting has emerged as a promising technology for directly converting waste heat into electricity through solid state, environmentally friendly means. Among copper chalcogenides, Cu2Te is a notable p-type material due to its degenerate semiconducting nature and low thermal conductivity. In this study, we present a sustainable synthesis strategy for Sn-doped Cu2Te referred to as bronze telluride (BT) via a chemical vapor deposition (CVD) assisted tellurization process using pre-alloyed Cu Sn (bronze) powder. The resulting BT exhibited an enhanced thermoelectric figure of merit (ZT) of 1 at 500 K. To assess practical applicability, BT was integrated with n type galena (PbS) in a cascaded p n thermoelectric module, which generated 2.8 mV across a temperature gradient of 35 K, demonstrating its potential for medium- to high-temperature waste heat recovery. Furthermore, thermodynamic calculations and density functional theory (DFT) simulations provided insights into the formation mechanism of Cu2Te and the thermoelectric behaviour of BT. This work introduces an efficient, scalable, and environmentally responsible pathway for developing copper-based thermoelectric materials using industrially relevant precursors.