Manipulating the Architecture of Atomically Thin Transition Metal (Hydr)oxides for Enhanced Oxygen Evolution Catalysis [component]

Graphene-like nanomaterials have received tremendous research interest due to their atomic thickness and fascinating properties. Previous studies mainly focus on the modulation of their electronic structures, which undoubtedly optimizes the electronic properties, but is not the only determinant of performance in practical applications. Herein, we propose a generalized strategy to incrementally manipulate the architectures of several atomically thin transition metal (hydr)oxides, and 2 study
more » ... r effects on catalytic water oxidation. The results demonstrate the obvious superiority of a wrinkled nanosheet architecture in both catalytic activity and durability. For instance, wrinkled Ni(OH)2 nanosheets display a low overpotential of 358.2 mV at 10 mA cm -2 , a high current density of 187.2 mA cm -2 at 500 mV, a small Tafel slope of 54.4 mV dec -1 , and excellent long-term durability with gradually optimized performance, significantly outperforming other nanosheet architectures and previously reported catalysts. The outstanding catalytic performance is mainly attributable to the 3D porous network structure constructed by wrinkled nanosheets, which not only provides sufficient contact between electrode materials and current collector, but also offers highly accessible channels for facile electrolyte diffusion and efficient O2 escape. Our study provides a perspective on improving the performance of graphene-like nanomaterials in a wide range of practical applications. The successful fabrication and use of graphene has stimulated extensive exploration of atomically thin two-dimensional (2D) nanomaterials for both fundamental studies and practical applications. 1-5 To date, many atomically thin 2D nanomaterials, such as hexagonal boron nitride, 6,7 graphitic carbon nitride, 8, 9 black phosphorous, 10,11 layered double hydroxides, 12,13 transition metal dichalcogenides, 14,15 metalorganic frameworks, 16,17 covalent-organic frameworks, 18, 19 and MXenes, 20, 21 have been successfully developed by liquid exfoliation or wet-chemical synthesis. 22-25 These nanomaterials with atomic/molecular thickness possess large specific surface areas, exotic electronic properties, excellent mechanical flexibility, and high optical transparency, and consequently they are promising for applications in sensors, energy conversion and storage, biomedicine, (opto)electronics, etc. 14,26-28 With the purpose of further improving their performance, considerable attention has been devoted to the rational design of nanostructures with the desired physical and chemical properties, 29 via thickness
doi:10.1021/acsnano.7b08691.s001 fatcat:si2jkbj4rvhsxm7s3dxbk2ia4i