Hierarchically nanostructured MoS2 with rich in-plane edges as a high-performance electrocatalyst for the hydrogen evolution reaction. Issue 38 (25th August 2016)

• Record Type: Journal Article
• Authors: Huang, Haoliang; Chen, Liqin; Liu, Chuanhe; Liu, Xinshun; Fang, Senxuan; Liu, Weipeng; Liu, Yingju
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 38(2016)
• Page Start: 14577
• Page End: 14585
• Publication Date: 2016-08-25
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta06174e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Hierarchical MoS2 with a rich in-plane edge nanostructure is synthesized and exhibits surging HER activity with a low onset potential and Tafel slope. Abstract : As a low-cost and earth-abundant electrocatalyst for the hydrogen evolution reaction (HER), molybdenum sulfide (MoS2 ) is recognized as a two dimensional material composed of catalytically active edges and an inert basal plane. Thus, optimizing simultaneously the hierarchical nanostructure and active site density could substantially improve its HER activity but it is not an effortless strategy to do so. Herein, we report for the first time a facile and controllable synthesis for engineering hierarchically nanostructured MoS2 nanosheets with rich in-plane edges (IE-MoS2 NSs). The IE-MoS2 NSs feature HER-oriented nanostructures with a tiny size, few-layer, expanded interlayer spacing and an unconventional in-plane-edge structure where separated MoS2 nanoflakes stand on the basal plane of nanosheets. Defects (Mo species with multiple chemical states and oxygen heteroatoms) were identified and they were proposed to be responsible for stabilizing the highly active MoS2 nanoflakes, forming the unique in-plane edges. IE-MoS2 NSs exhibit surprisingly high HER activity with a low onset potential of −87 mV and a Tafel slope of 41 mV per decade, exceeding other nanostructured MoS2 materials in this work and surpass almost all documented MoS2 -based electrocatalysts. The surging activity has been discussed in detail, showing that the in-plane-edge nanostructure boosts the number of catalytic sites and promotes the intrinsic activity of each site at the same time, facilitating the catalytic process for H2 evolution.