Two-Dimensional Mn-Co LDH/Graphene Composite towards High-Performance Water Splitting

• Main Authors: Jian Bao, Junfeng Xie, Fengcai Lei, Zhaolong Wang, Wenjun Liu, Li Xu, Meili Guan, Yan Zhao, Huaming Li
• Format: Article
• Language: English
• Published: MDPI AG 2018-08-01
• Series: Catalysts
• Subjects: ultrathin structure; oxygen evolution reaction; graphene; two-dimensional; layered double hydroxide
• Online Access: http://www.mdpi.com/2073-4344/8/9/350

The oxygen evolution reaction (OER) is a complex multi-step four-electron process showing sluggish kinetics. Layered double hydroxides (LDH) were reported as promising catalysts for the OER, but their low electrical conductivity restricts their widespread applications. To overcome this problem, a composite material containing Mn-Co LDH ultrathin nanosheet and highly conductive graphene was synthesized for the first time. Benefited from the high electrocatalytic activity and the superior charge transfer ability induced by these components, the new material shows superior OER activity. Used as the OER catalyst, a high current density of 461 mA cm−2 at 2.0 V vs. RHE (reversible hydrogen electrode) was measured besides shows a low overpotential of 0.33 V at 10 mA cm−2. Moreover, the new composite also shows a superior bifunctional water splitting performance as catalyst for the OER and HER (hydrogen evolution reaction) catalysts. Our results indicate that the presented material is a promising candidate for water splitting which is cheap and efficient.