Utilizing Waste Heat to Drive Selective Green Organic Conversion through a Thermoelectrocatalytic Process

Utilizing waste heat from environmental or industrial sources is a promising strategy for eco-friendly and sustainable chemical synthesis. Here, a pioneering thermoelectrocatalytic (TECatal) system that can harness minimal heat diffusion for selective organic conversions is demonstrated. The proof-of-concept demonstrates a TECatal nanohybrid consisting of a thermoelectric (TE) Bi₂Te₃ nanoflake core with a Fe-doped UiO-66 metal-organic framework shell (Bi₂Te₃/Fe-UiO-66). This nanohybrid catalyst significantly enhances H₂O₂ production in water at small temperature differences (≈10-60 K) and enables a unique TECatal-Fenton-like process, effectively converting benzyl alcohol into benzaldehyde. This process leverages H₂O₂ generated via the TECatal effect to react with Fe²⁺ in the Fe-UiO-66, producing highly active •OH radicals for selective oxidation. The Fe-UiO-66 coating exhibits triple functionality: separating TE-generated charges, enhancing surface active sites, and preventing Bi₂Te₃ oxidation. Scaling up this catalysis to a 2 L volume, powered solely by a low-temperature waste heat source (ΔT = ≈50 K), demonstrates continuous production of benzaldehyde with a high conversion ratio of 81.3% and superior selectivity of over 99% in 8 h. This successful endeavor highlights the great potential of TE nanomaterials in recycling waste thermal energy for green chemistry, marking a significant advancement toward economical and sustainable practices.