Metal sulphide CuS and CdS nanoparticles capped with Cetyltrimethylammonium bromide (CTAB) were synthesized by hydrothermal method. Structural, morphological, chemical composition, optical and luminescent properties were evaluated by different analytical techniques. X-ray diffraction (XRD) analysis of the CTAB capped metal sulfide nanoparticles reveals the formation of hexagonal structure. High-resolution transmission electron microscopy (HRTEM) images show that the morphology of the capped copper sulphide samples consists of hexagonal structure and capped cadmium has spherical shape and also confirms the crystalline nature of the particles with distinct lattice fringes. In FTIR spectroscopy, the composition of the CTAB capped CuS and CdS nanoparticles have been confirmed. The analysis of photoluminescence (PL) and optical transition show a red shift due to the reduction of band gap energy and it is attributed to the low defects and high crystallinity. The optical studies indicate that CuS and CdS nanoparticles with CTAB can be suitable for optoelectronic devices and photovoltaic applications.

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In this work, novel CeO 2 /CoWO 4 heterostructured nanocomposites (NCs) were synthesized via a hydrothermal method. X-ray diffraction, high-resolution transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy and photoluminescence spectroscopy were carried out to determine the crystal structure, deep morphology, optical properties, and charge separation of the obtained photocatalysts (PCs), respectively. In comparison to the pristine CoWO 4 , the CeO 2 and CeO 2 /CoWO 4 PCs demonstrated enhanced activity of methylene blue (MB) aqueous dye photodegradation under visible-light exposure. The photodegradation efficiency of the as-prepared CeO 2 /CoWO 4 photocatalyst showed the premier decomposition ratio (92.5%) of MB dye in 105 min among all samples, which was notably 1.8-fold and 2.2-fold that of the pristine CeO 2 (43%) and CoWO 4 (60%), respectively. Likewise, the CeO 2 / CoWO 4 PCs retained satisfactory photo-reactivity even after five sequential recycling runs, indicating their excellent photocatalytic stability and robustness. Hence the succeeding superior PCs preferred further efficient charge (e À -h + ) separation, excellent visible-light absorption, and worthy interfacial energy transfer leads between CoWO 4 and CeO 2 nanoparticles. Additionally, a plausible mechanism for the photodegradation was proposed. The synergistic antibacterial properties of the CeO 2 /CoWO 4 NCs were investigated by a gel diffusion method. Therefore, this work offers a novel avenue for the preparation of stable and efficient visible-light-driven PCs for environmental remediation.

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In this revision, a series of novel visible-light-driven (VLD) CeO2/PbWO4 nanocomposites (NCs) were effectively fabricated by facile hydrothermal preparation way. The UV–Vis absorption spectra exposed that CeO2 NPs prolonged the adsorption edge of the CeO2/PbWO4 composite to the extensive visible region, which allied to decreases of the bandgap. As-prepared CeO2/PbWO4 NCs revealed superior photocatalytic action under visible-light and could degrade the Methylene Blue (MB) dye solution in 140 min. The photodegradation efficacy of CeO2/PbWO4 NCs was improved catalytic activity, which is around 1.45 and 2.7 times that of CeO2 and PbWO4 nanoparticles (NPs) individually. Besides, the CeO2/PbWO4 catalysts display notable stability and reusability performance in four succeeding cycles. The development in the photocatalytic enactment of combined CeO2/PbWO4 nanocomposite could be recognized not only to the sturdy visible-light absorption responses and separating the photoexcited electron–hole pairs. Also, the plausibly systematic illumination of charge transference and exploitation of reactive species for superior photocatalytic action in visible-light have been discussed. It is projected that the CeO2/PbWO4 NCs could be used as effective photocatalysts for promising applications for environmental wastewater refinement.