Generating Electrical Power from Low-Grade Waste Heat through Thermoelectrochemical Cells Utilizing Titanium Carbide Electrodes

In response to growing environmental concerns and the limitations of traditional carbon-based fuels, there has been significant research into sustainable energy resources, particularly those that harness ambient energy sources such as thermal, wind, kinetic, and solar energy. However, efficiently harvesting low-grade waste heat, produced by sources like power plants and environmental body heat, has remained a challenge due to the cost and inefficiency of large-scale thermal energy conversion devices. Thermoelectrochemical cells (TECs) are highly effective devices for converting low-grade waste heat into electricity. However, TECs that rely on hexacyanoferrate (Fe(CN)64–/Fe(CN)63–, HCF) electrodes often use expensive metals like platinum (Pt), which hinders their practical use. In this study, we propose an alternative to Pt electrodes for TECs in the form of titanium carbide (TiC) electrodes, synthesized through the thermal decomposition of CH4. While titanium itself is challenging to use in TECs, TiC emerges as a promising non-noble metal electrode due to its exceptional stability and reaction kinetics, suitable for various electrochemical systems. Our experiments revealed that TiC-based TECs achieved a power output of 397.20 mW m–2, nearly matching that of Pt electrodes. Additionally, TiC demonstrated long-term stability in the electrolyte during operation, suggesting its potential to replace Pt electrodes and facilitate the commercialization of TECs.