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The use of graphene‐based composite as anti‐corrosion and protective coatings for metallic materials is still a provocative topic worthy of debate. Nickel–graphene nanocomposite coatings have been successfully fabricated onto the mild steel by electrochemical co‐deposition technique. This research demonstrates the properties of nickel–graphene composite coatings influenced by different electrodeposition current densities. The effect of deposition current density on the; surface morphologies, composition, microstructures, grain sizes, mechanical, and electrochemical properties of the composite coatings are executed. The coarseness of deposited coatings increases with the increasing of deposition current density. The carbon content in the composite coatings increases first and then decreases by further increasing of current density. The improved mechanical properties and superior anti‐corrosion performance of composite coatings are obtained at the peak value of current density of 9 A dm−2. The incorporation of graphene sheets into nickel metal matrix lead to enhance the micro hardness, surface roughness, and adhesion strength of produced composite coatings. Furthermore, the presence of graphene in composite coating exhibits the reduced grain sizes and the enhanced erosion–corrosion resistance properties.

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Fuel cell technology is the supreme alternate option for the replacement of fossil fuel in the current era. Pt alloys can perform well as fuel cell electrodes for being used as catalytic materials to perform the very notorious oxygen reduction reaction. In this regard, first, a layered metal− organic framework with empirical formula [C 8 H 10 CdO 7 ] n • 4H 2 O is synthesized and characterized using various experimental and theoretical techniques. Then, a nanostructured porous carbon material with a sheet morphology (PC900) having a high BET surface area of 877 m 2 g −1 is fabricated by an inert-atmosphere thermal treatment of the framework upon heating up to 900 °C. Pt and Ni nanoparticles are embedded into PC900 to prepare a homogenized hybrid functional material, i.e.,

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Plant-based materials are reported to have a wide range of applications in the environmental and biomedical sectors. In this report, we present an economic and environmentally friendly supported turmeric powder (TP) biomass for the support of Ag, Ni and Cu nanoparticles (NPs) designated as Ag@TP, Ni@TP and Cu@TP. The in situ syntheses of the stated NPs were achieved in aqueous medium using NaBH4 as a reducing agent. The prepared NPs were applied for the degradation of o-nitrophenol (ONP), m-nitrophenol (MNP), p-nitrophenol (PNP), methyl orange (MO), Congo red (CR), rhodamine B (RB) and methylene blue (MB). Initially, Ag@TP, Ni@TP and Cu@TP were screened for the MO dye and antibacterial activity, where Ag@TP displayed the strongest catalytic activity for MO and bactericidal activities as compared to Ni@TP and Cu@TP. The quantity of metal ions adsorbed onto the TP was investigated by atomic absorption spectroscopy. The Ag@TP, Ni@TP and Cu@TP were characterized through X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, thermal gravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDS) and field emission scanning electron microscope (FESEM) analysis.

Three new isostructural chiral silver-lanthanide heterometal-organic frameworks [AgLn(μ-OH)(bpdc)(NO)(HO)](NO)·2HO [Ln = Eu (1), Tb (2, Sm (3); Hbpdc = 2,2'-bipyridine-3,3'-dicarboxylic acid] based on heptanuclear lanthanide clusters [Ln(μ-OH)] comprised of one-dimensional triple right-handed helical chains were hydrothermally synthesized. Various means such as UV-vis spectroscopy, IR spectroscopy, elemental analysis, powder X-ray diffraction, and thermogravimetric/differential thermal analysis were used to characterize the compounds, wherein compound 3 was crystallographically characterized. In the structure of compound 3, eight μ-OH groups link seven Sm ions, forming a heptanuclear cluster, [Sm(μ-OH)], and the adjacent [Sm(μ-OH)] clusters are linked by the carboxylic groups of bpdc ligands, leading to the formation of a one-dimensional triple right-handed helical chain. The adjacent triple right-handed helical chains are further joined together by coordinating the pyridyl N atoms of the bpdc ligands with Ag, resulting in a chiral three-dimensional silver(I)-lanthanide(III) heterometal-organic framework with one-dimensional channels wherein NO anions and crystal lattice HO molecules are trapped. The compounds were studied systematically with respect to their photoluminescence properties and energy-transfer mechanism, and it was found that Hbpdc (the energy level for the triplet states of the ligand Hbpdc is 21505 cm) can sensitize Eu luminescence more effectively than Tb and Sm luminescence because of effective energy transfer from bpdc to Eu under excitation in compound 1.