الفهرس 
Experimental TechniquesOnly 14 pages are availabe for public view
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Abstract
Manganite containing La is a promising perovskite material as it has wide range of applications. In this piece of work, nanoparticles of La1−xAgxMnO3 samples (0.00 ≤ x ≤ 0.09) were synthesized using wet chemical method. The samples were characterized by thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), differential thermal analysis (DTA), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), infrared spectroscopic (FT-IR), and differential scanning calorimetry (DSC). The XRD study showed that all samples adopted the rhombohedral / hexagonal structure with a space group of R-3 ̅c (167). The HR-TEM/FE-SEM images showed that the perovskite structure were successfully obtained. Investigation of the magnetic properties was conducted in a wide range of temperature to confirm the ferromagnetic-paramagnetic (FM-PM) presence around Curie temperature (Tc ≈ 270 K). The shift of the Curie point to larger values was clearly observed for the samples by increasing the silver contents. The optical properties were examined by ultraviolet visible (UV) diffuse reflectance spectroscopy. The pore volume, pore size, and surface area were calculated and examined. The prepared samples were used as a photoanode in alkaline media for water splitting, and the photocurrent was measured. The photocurrent density recorded at 1 V vs. Ag/AgCl (14.01, 12.02, 11.67, and 10.28 μA/cm2) for x = (0.09, 0.06, 0.03, and 0.00), respectively. The impedance of the sample (x = 0.09) photoanodes smaller than the sample (x = 0.00), which displayed a considerable decrease in charge transfer resistance. The electron lifetime (τ) increased with increasing Ag concentration, where x = 0.09 has the largest electron lifetime (τ) = 10.04 m.sec. Therefore, the electron–hole recombination rate of La0.91Ag0.09MnO3 is lower than LaMnO3. The samples demonstrated long term stability for 1 h and enhanced photoelectrochemical performance.