Co−Mo−S Nanoflowers Wrapped Oxidized Multi‐Walled Carbon Nanotubes as Efficient Electrocatalysts for Oxygen Evolution Reaction

Abstract Developing highly active and stable earth‐abundant electrocatalysts for water splitting is of prime importance for renewable energy conversion systems. Herein, we develop a facile hydrothermal process to prepare nanoflowers by compounding Co−Mo−S and oxidized multi‐walled carbon nanotubes (denoted as Co1.5Mo1.0S/o‐MWNTs) as efficient oxygen evolution reaction (OER) catalysts. Oxidized MWNTs could enhance the hydrophilicity and electrical conductivity of the catalyst conductivity. Co and Mo charge transfer can be accelerated after the chemical hybridization of Co, Mo and highly conductive o‐MWNTs. Co is easily oxidized into cobalt oxyhydroxide, which acts as the active site for OER. The electrocatalyst exhibits highly efficient electrocatalytic performances, achieving low overpotential of 311 mV for the OER at current density of 10 mA cm−2 and low Tafel slope of 70 mV dec−1 in alkaline media. The catalyst maintains good stability even after 10 hours of chronoamperometry test at 1.60 V in alkaline solution. This work provides a new direction for boosting the electrocatalytic activity through coupling bimetallic sulfides and constructing with conductive substrate.