Value‐added formate production from selective ethylene glycol oxidation based on cost‐effective self‐supported MOF nanosheet arrays
Lei Jiao, Wenbo Wei, Xiaofang Li, Cheng‐Bin Hong, Shu‐Guo Han, Muhammad Imran Khan, Qi‐Long Zhu
Abstract
In order to realize electrochemical upgrading and improve the energy conversion efficiency, an ingenious strategy of constructing a thermodynamically favorable oxidation reaction to replace oxygen evolution reaction (OER) is proposed. Here we report the self‐supported NiCo‐based metal–organic framework (MOF) nanosheet arrays grown on a stainless‐steel mesh (NiCo‐SS), which can be used as a highly efficient and cost‐effective electrocatalyst for ethylene glycol oxidation reaction (EGOR) coupling with hydrogen evolution reaction (HER) in the pair‐electrolysis system to concurrently produce value‐added formate and high‐purity hydrogen. Impressively, the required potential for EGOR at the anode is 200 mV lower than that for OER to deliver the same current density of 100 mA·cm −2 . In addition, the pair‐electrolysis of selective ethylene glycol oxidation and hydrogen evolution only requires a quite low voltage of 1.68 V to achieve the current density of 50 mA·cm −2 in the membrane‐free dual‐electrode electrolytic cell, 200 mV smaller than that for overall water splitting. Moreover, Faradaic efficiencies of over 80% for formate production have been obtained. This work indicates that it is prospective to employ earth‐abundant electrocatalysts to concurrently produce high‐purity hydrogen and value‐added formate, which would be a promising technology for supplying clean and renewable energy.