Synergistic cerium doping and MXene coupling in layered double hydroxides as efficient electrocatalysts for oxygen evolution

• 来源期刊: 能源化学
• 年，卷（期）: 2021,（1）
• 页码范围: 412-420
• 页数: 9页
• 语种: 英文

摘要

Oxygen evolution reaction(OER)is a bottle-neck process in many sustainable energy conversion systems due to its sluggish kinetics.The development of cost-effective yet efficient electrocatalysts towards OER is highly desirable but still a great challenge at current stage.Herein,a new type of hybrid nanostruc-ture,consisting of two-dimensional(2D)Cerium-doped NiFe-layered double hydroxide nanoflakes directly grown on the 2D Ti3C2Tx MXene surface(denoted as NiFeCe-LDH/MXene),is designed using a facile in-situ coprecipitation method.The resultant NiFeCe-LDH/MXene hybrid presents a hierarchical nanoporous structure,high electrical conductivity and strong interfacial junction because of the synergistic effect of Ce doping and MXene coupling.As a result,the hybrid catalyst exhibits an excellent catalytic activity for OER,delivering a low onset overpotential of 197 mV and an overpotential of 260 mV at a current density of 10 mA?cm-2 in the alkaline medium,much lower than its pure LDH counterparts and Ir02 catalyst.Besides,the hybrid catalyst also displays a fast reaction kinetics and a remarkable stable durability.Fur-ther theoretic studies using density function theory(DFT)methods reveal that Ce doping could effectively narrow the bandgap of NiFe-LDH and reduce the overpotential in OER process.This work may shed light on the exploration of advanced electrocatalysts for renewable energy conversion and storage systems.