Hierarchical ultrathin layered MoS2@NiFe2O4 nanohybrids as a bifunctional catalyst for highly efficient oxygen evolution and organic pollutant degradation.

[Display omitted] • Ultrathin MoS 2 @NiFe 2 O 4 is constructed by a facile hydrothermal and amine-hydrolysis. • MS@NiFeO delivers highly efficient OER performance and photodegradation activity. • Stability and reuse of MS@NiFeO are quite stable and remain little change. • The *OH and *O 2 − reactive species confirms the photocatalytic mechanism by ESR spectroscopy. Rational design and highly efficient dual-functional catalyst are still difficult to develop for electrocatalytic oxygen evolution reaction and degradation of RhB dye pollutant. Herein, we report a highly efficient "bandgap matching and interfacial coupling" strategy to synthesize nano-assembled ultrathin layered MoS 2 @NiFe 2 O 4 (MS@NiFeO) bifunctional catalyst constructed by the hydrothermal route and subsequently amine-hydrolysis. The OER performance of the prepared MS@NiFeO catalyst delivers a low overpotential of 290 mV at 10 mA/cm2 and Tafel slope is 69.2 mV dec−1 in an alkaline solution. In addition, the nano-assembled ultrathin layered structure of MS@NiFeO showed a highly efficient (96.37%) RhB dye degradation performance than that of MoS 2 nanosheets and NiFe 2 O 4 nanostructures. Unique nanostructure of ultrathin layered MS@NiFeO with suitable band matching, interfacial charge transfer, high surface area and more active sites favored for the enhancement of the catalytic activity. This work presents an unpretentious construction and low-cost production strategy to synthesize bifunctional hybrid catalyst for oxygen evolution reaction as well as degradation of organic pollutant with superior efficiency and longer stability. [ABSTRACT FROM AUTHOR]