CoP2/Fe-CoP2 yolk–shell nanoboxes as efficient electrocatalysts for the oxygen evolution reaction

• Published in: Nanoscale Vol. 13; no. 8; pp. 4569 - 4575
• Main Authors: Ganesan, Vinoth, Son, Jihye, Kim, Jinkwon
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.01.2021
• Subjects: Chemical composition; Electrocatalysts; Hydrogen fuels; Metal-organic frameworks; Moisture content; Oxygen evolution reactions; Pigments; Scanning electron microscopy; Water splitting; Zeolites
• ISSN: 2040-3364; 2040-3372; 2040-3372
• DOI: 10.1039/d0nr08108f

The development of an efficient electrocatalyst is an important requirement for water splitting systems to produce clean and sustainable hydrogen fuel. Herein, we synthesized CoP2/Fe-CoP2 yolk–shell nanoboxes (YSBs) as efficient electrocatalysts for the oxygen evolution reaction (OER). Initially, zeolitic imidazolate framework-67/CoFe-Prussian blue analogue (ZIF-67/CoFe-PBA) YSBs were prepared by the reaction of ZIF-67 and [Fe(CN)6]3− ions in the presence of a small amount of water as an etching agent. The size of the CoP2 yolk depends on the amount of water. The heteronanostructure composed of the CoP2 yolk and the FexCo1−xP2 shell with a cubic shape was obtained by phosphidation of ZIF-67/CoFe-PBA YSBs. Benefiting from the unique structure and chemical composition, the CoP2/Fe-CoP2 YSB electrocatalyst has a large specific surface area of 114 m2 g−1 and shows superior electrocatalytic performances for the OER such as a low overpotential of 266 mV, a small Tafel slope value of 68.1 mV dec−1, and excellent cyclic stability.