UV–visible light sensitized NiCo 2 O 4 @g–C 3 N 4 heterojunction: Based nanocomposites as novel photocatalysts for enhanced hydrogen generation and electrochemical activity

Herein , a novel thermal decomposition approach for the synthesis of NiCo 2 O 4 @g–C 3 N 4 heterojunction based nanocomposites has been described. Morphology, structural data and bonding parameters of the prepared material was elucidated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDXA), transmission electron microscopy (TEM), X-ray photoelectron microscopy (XPS), and UV–visible diffuse reflectance (DRS-UV–visible) microscopy. After characterization, the nanocomposites were explored as effective photocatalysts for hydrogen (H 2 ) generation through water splitting under UV–visible light (solar simulators) irradiation. The maximum H 2 production (3,533 and 2,560 μmol.h −1 .g cat −1 ) rate achieved using NiCo 2 O 4 @g–C 3 N 4 nanocomposite catalysts were significantly higher than that of pristine g-C 3 N 4 (2,056 μmol.h −1 .g cat −1 ), and NiCo 2 O 4 (2,334 μmol.h −1 .g cat −1 ) catalysts. Furthermore, the electrochemical performances of the synthesized nanocomposites were investigated by cyclic voltammetry and also their effectiveness has been tested with pristine NiCo 2 O 4 nanoparticles. Graphical abstract Schematic illustration of fabrication and possible photogenerated charge carriers transfer route for NiCoO 4 /g–C 3 N 4