Constructing heterostructured CoSe2/Ni3Se4@N-doped carbon nanosheets/ketjen black carbon as a robust oxygen evolution electrocatalyst

Abstract We design and construct a novel heterostructured CoSe2/Ni3Se4@N-doped carbon nanosheets/Ketjen black carbon (denoted as CoSe2/Ni3Se4@NC/KB) via the combination of pyrolysis and hydrothermal method. As a result of the exceptional synergism between CoSe2 and Ni3Se4 as well as high conductivity of carbon materials, the obtained CoSe2/Ni3Se4@NC/KB drives an OER current density of 10 mA cm−2 by an overpotential of 260 mV and displays a low Tafel slope of 68 mV dec−1, outmanoeuvring commercial RuO2 and IrO2, control groups (i.e. Ni3Se4@NC/KB, CoSe2@NC/KB, and CoSe2/Ni3Se4@NC), as well as most hybrids of selenides and carbon materials reported recently.