Synthesis of a flower-like MoS2/carbon nanocomposite with enhanced adsorption performance toward Eu(iii): the cooperative effects between S atoms and carboxyl groups

Abstract

The hazardous consequences that the radionuclide europium (Eu(III)) has on humanity and the ecological environment motivate the development of advanced sorbent materials for its efficient removal from wastewater. Herein, a flower-like molybdenum disulfide material fabricated using a carbon composite (MoS₂/C) was successfully prepared via an in situ hydrothermal method and confirmed using various experimental characterization methods (scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy). It was found that the MoS₂/C composite exhibits a much higher sorption capacity (100.57 mg g⁻¹, pH 5.0, 298 K) towards Eu(III) than that of pristine MoS₂ (32.52 mg g⁻¹, pH 5.0, 298 K) due to the cooperative effects between the S atoms of MoS₂ and carboxyl groups of the carbon material, which were confirmed from X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. Besides this, the MoS₂/C exhibited a high adsorption rate with a short equilibrium time (120 min) and a wide pH operating range (4.0–9.0). This study reveals that the MoS₂/C composite can be employed as an auspicious candidate for Eu(III) removal and expands the realm of possibilities of using MoS₂-based materials in the field of eliminating radionuclides from wastewater.