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Abstract: This study reports the successful hydrothermal synthesis of high-quality 1T´/2H mixed phase molybdenum disulfide (MoS2) three-dimensional (3D) microspheres in a highly alkaline medium under optimized synthesis parameters. MoS2 nanostructures have gained significant interest due to their unique properties and potential applications in electronics, optoelectronics, environmental remediation and energy storage devices [1] [2]. The as-synthesized material demonstrates superior performance in the removal of water soluble organic dyes through adsorption and photodegradation under natural sunlight. The structural, optical and morphological features of 1T´/2H MoS2 microspheres were characterized by X-ray diffraction (XRD), Field-emission scanning electron microscopy (FESEM), Fourier transform Infrared spectroscopy (FTIR), photoluminescence (PL), UV-Visible spectroscopy and Raman spectroscopy. Batch adsorption studies and photocatalytic degradation of water soluble organic dyes using 1T´/2H MoS2 microspheres was carried out for both cationic and anionic organic dyes - methylene blue (MB) and methyl orange (MO). An adsorption capacity of up to 147.11 mg/g at a dye concentration (MB) 40 mg/L was achieved, with superior removal rate above 90% for all dye concentrations within 106 minutes. The adsorption kinetics study revealed that adsorption of methylene blue dye onto the MoS2 microspheres surface followed pseudo second order kinetics and the adsorption isotherm at equilibrium was described by both Langmuir and Freundlich models, suggesting that the 1T´/2H MoS2 microspheres surface consists of a combination of homogeneous and heterogeneous sites. The 1T´/2H MoS2 microspheres exhibited significant improvements in the photodegradation of both cationic and anionic dyes – methylene blue (MB) and Methyl orange (MO) dyes, achieving 96% and 90% degradation within 35 and 80 minutes. The excellent removal efficiency and superior photocatalytic degradation are attributed to the 1T´/2H mixed phase structure and the hierarchical MoS2 microsphere-like morphology.
