One Nanometer PtIr Nanowires as High-Efficiency Bifunctional Catalysts for Electrosynthesis of Ethanol into High Value-Added Multicarbon Compound Coupled with Hydrogen Production

The electrosynthesis of high-value-added multicarbon compounds coupled with hydrogen production is an efficient way to achieve carbon neutrality; however, the lack of effective bifunctional catalysts in electrosynthesis largely hinders its development. Herein, we report the first example on the highly efficient electrosynthesis of high-value-added 1,1-diethoxyethane (DEE) at the anode and high-purity hydrogen at the cathode using 1 nm PtIr nanowires (NWs) as the bifunctional catalysts. We demonstrate that the cell using 1 nm PtIr nanowires as the bifunctional catalysts can achieve a reported lowest voltage of 0.61 V to reach the current density of 10 mA cm^-2, much lower than those of the Pt NWs (0.85 V) and commercial Pt/C (0.86 V), and also can have the highest Faraday efficiencies of 85% for DEE production and 94.0% for hydrogen evolution in all the reported electrosynthesis catalysts. The in situ infrared spectroscopy study reveals that PtIr NWs can facilitate the activation of O-H and C-H bonds in ethanol, which is important for the formation of acetaldehyde intermediate, and finally DEE. In addition, the cell using PtIr NWs as bifunctional catalysts exhibits excellent stability by showing almost no obvious decrease in the Faraday efficiency of the DEE production.