Bi ‐Functional Fe3O4/Au/CoFe‐LDH Sandwich‐Structured Electrocatalyst for Asymmetrical Electrolyzer with Low Operation Voltage

A bi-functional Fe3O4/Au/CoFe-LDH sandwich-structured catalyst is used in an asymmetrical electrochemical cell for electrocatalytic hydrogen evolution reaction (HER) and glucose oxidation reaction (GOR) in alkali solution. 10  mA cm−2 current density is achieved by a cell voltage of 0.48  V. 89.7% selectivity of GOR is maintained even at 1000 mA cm−2. AbstractThe reduction of the overall electrolysis potential to produce hydrogen is a critical target for fabricating applicable hydrogen evolution cells. Sandwich-structured Fe3O4/Au/CoFe-LDH is synthesized via a spontaneous galvanic displacement reaction. A series of structural characterizations indicate the successful synthesis of sandwich-structured Fe3O4/Au/CoFe-LDH electrocatalyst. The trace amount of Au laying between Fe3O4 and CoFe-LDH significantly improves the intrinsic conductivity and catalytic activity of the composite catalyst. In-depth investigations indicate that Fe3O4 and CoFe-LDH are responsible for the electrocatalytic hydrogen evolution reaction (HER) whereas Au is responsible for the electrocatalytic glucose oxidation (GOR). The electrocatalytic tests indicate Fe3O4/Au/CoFe-LDH offers excellent electrocatalytic activity and stability for both HER and GOR, even at high current density (i.e., 1000  mA cm−2). Further electrochemistry examinations in a two-compartment cell with a two-electrode configuration show that Fe3O4/Au/CoFe-LDH can significantly reduce the overall potential for this asymmetrical ...

Source: Small - October 16, 2021 Category: Nanotechnology Authors: Fengchao Sun, Yan Zhou, Zihan You, Hanhan Xia, Yongxiao Tuo, Shutao Wang, Cuiping Jia, Jun Zhang Tags: Research Article Source Type: research