Carbon fiber paper supported interlayer space enlarged Ni2Fe-LDHs improved OER electrocatalytic activity

Herein, a series of three-dimensional Ni2Fe-SDS-LDH/CFP non-precious metal electrocatalysts in a simple hydrothermal route using sodium dodecyl sulfonate (SDS) as an interlayer spacer agent, and carbon fiber paper (CFP) as a conductive substrate was tailored. The electrocatalytic performance towards oxygen evolution reaction (OER) in alkaline medium was investigated. The results demonstrate that the OER activity improvement is mainly related to the increased interlayer distance from 0.76 nm to 2.49 nm depending on the intercalated amount of SDS in Ni2Fe-LDH, and resulting in the enhanced superior surface characteristics (e.g., larger specific surface area, bigger pore size and pore volume). Among all the samples, the Ni2Fe-SDS-LDH/CFP (molar ratio SDS/Fe = 1.5) showed the best OER performance (η@10 mA cm−2 = 289 mV, Tafel slope = 39 mV dec−1) comparable with the commercial IrO2 catalyst, which corresponded to the largest interlayer space of 2.49 nm.