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Harvesting solar light efficiently and effective photo‐induced charge separated photocatalysts becoming an immense demand for environment salvation. Herein, the one‐step solvothermal method has been employed to synthesize Zn1–xRuxS nanoparticles (NPs). A systematic study for the photocatalytic degradation of Methylene blue (MB) for the first time in Ru doped ZnS system has been carried out with visible light (LED) irradiation. Density functional theory has been employed to study the structural, electronic properties and charge transfer mechanism throughout the Ru doped ZnS system. Theoretical results and UV‐Vis spectra suggest a reduction of bandgap as a function of Ru concentration. Bader charge analysis for both the structures as well as photoluminescence quenching has shown Ru acts as a charge center in the charge transfer process. The optimum photodegradation efficiency is achieved in case of 1% Ru doped ZnS NPs. Thus Ru doping in ZnS NPs has a significant role in showing effective photocatalytic behaviour.

Pristine Antimony tungstate nanoparticles prepared via a simple hydrothermal process showcase interesting photocatalytic efficiency, degrading Methylene Blue (MB) completely in 180 min under visible light. In this study, the impact on crystalline quality and related optical properties as well as photocatalytic efficiency of antimony tungstate due to temperature variation during hydrothermal synthesis are explored. While X-ray diffraction (XRD) shows the polycrystalline nature of all synthesized samples, however a systematic increase in crystallite size is revealed by analysing the XRD peak broadening. XRD spectra are further examined by Rietveld analysis showing a change in unit cell volume. Additionally, the overall changes in the corresponding grain size and micro-strain developed in the crystals are determined using the Williamson-Hall plot. Moreover, significant variations in few Raman modes are observed with increasing synthesis temperature. A notable modification in the optical band gap as determined from the absorbance of the UV-Vis spectra is perceived with the change in synthesis temperature within the range of ~2.38-2.57 eV. Further, the photoluminescence measurement indicates that the synthesized antimony tungstate is weak 2 luminescent material with a band-to-band emission at ~468 nm. Finally, photocatalytic efficiencies of the samples are ascertained to change with the synthesis parameter, estimated by decomposing methylene blue (MB), highest degradation rate constant (k) value is observed as 0.015 min -1 for the sample prepared at 180 o C. While the sample with the highest efficiency is also applied for degrading the Rhodamine B (RhB) and Potassium Dichromate (K2Cr2O7) under visible light irradiation.

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