Structural and optical study of Fe³⁺‐doped Al₂O₃ nanocrystals prepared by new sol gel precursors

Abstract

Pure and Fe-doped Al 2 O 3 nanoparticles (NPs) were synthesized with different iron doping percentage of 1, 3, and 5 mol% employing sol gel technique with AlCl 3 , FeCl 3 as well as ethylene glycol (EG) and Polyvinylpyrrolidone (PVP) stabilizers as precursors. The XRD results indicated that the hexagonal structure of Fe/Al 2 O 3 nanocomposite with alpha phase was formed by the substitution of Fe 3+ ions in the alumina network. The sizes of the NPs obtained for the pure samples and doped samples at percentage dopant of 5% were 35 and 28 nm, respectively.The results of FTIR optical analysis showed the vibrational bond at the wavelength of 448 cm −1 , indicating the Al-O band in the sample. The UV-DRS analysis showed that the energy band gap for the pure NPs was 4 eV, but with increase in iron dopant up to 5%, it decreased to 3.42 eV. In addition, the results of photoluminescence (PL) analysis demonstrated that with increase in doping percentage, the PL intensity diminished. VSM magnetic analysis showed that with increase in iron dopant, the ferromagnetic state emerged in the NPs at saturation magnetism of 0.136 emu/g. Finally, photocatalytic experimental results demonstrated that 5% Fe-doped Al 2 O 3 NPs effectively degrade MB approximately 53%. K E Y W O R D Salpha phase, catalyst, crystal structure, Fe/Al 2 O 3 nanocrystals, solgel, XRD

Infrared photodissociation spectroscopy of (Al2O3)2–5FeO+: influence of Fe-substitution on small alumina clusters

“…28 These observations are in line with the results for Fe-doped nanocrystals or nanoparticles, 12 in which dopant Fe atoms preferably replace Al atoms of the Al 2 O 3 network mostly in the surface layer 21 without inducing major distortions or even structural changes. 53 While structural deviations from the corresponding all-Al clusters are evident for the clusters with larger Fe : Al ratios ( n = 1–3), starting from Al 8 M O 13 + the cluster framework is virtually identical for M = Fe and Al, proving the suitability of iron as a dopant for Al 2 O 3 .…”

Advantages and Disadvantages of Chemical Methods in the Elaboration of Nanomaterials

“…In 2013 Shaker and his colleagues obtained sol gel magnetic nanoparticles (Fe3O4) technique and showed that the crystallinity was improved at a higher treatment temperature and therefore the particle agglomeration decreased dramatically [11]. Khodadadi and his colleagues developed sol-gel method of Al2O3 nanocrystals and Fe-doped Al2O3 nanocrystals [12]. Sun and his associates successfully reported soluble gel-soluble ZnO thin films at a relatively low temperature (≤200 °C), which can function as an efficient transport layer in inverted solar cells [13].…”

Effect of copper oxide (CuO) and vanadium oxide (V2O5) addition on the structural, optical and electrical properties of corundum (α-Al2O3)

“…Due to its stable thermodynamics, it is considered α-Alumina Oxide (α-Al 2 O 3 /corundum) one of the most important phase, α-Al 2 O 3 has a variety of applications, including ceramic, high-strength materials, transparent armor for ballistic performance, catalysts, catalyst support, adsorbents, and electronic matching like high-performance Field Effect Transistors (FETs), optoelectronics, electrical insulators, thermoluminescent dosimeters, light-emitting display, cutting tools, lasers, spark plugs, and gas sensor 1 , 3 – 5 . α-Al 2 O 3 is formed at temperatures above 1100 °C, with a hexagonal crystalline structure and lattice parameters a = 4.758 Å and c = 12.991 Å 6 , 7 . (α-Al 2 O 3 ) has direct energy transition and energy gap (E g ) 4.116 eV 5 8.8 eV 8 .…”

“…There are many studies that prepared pure α-Al 2 O 3 and doped with some metallic elements, but the prepartion of pure α-Al 2 O 3 as nanocomposite with copper oxide or vanaduim oxide was scarce,and from this point we sought to prepare pure α-Al 2 O 3 , α-,Al 2 O 3 /CuO(AC) and α-Al 2 O 3 /V 2 O 5 (AV) as a nanocomposite to improve the properties and search for its uses in many other applications. There are many methods used to prepare oxides as pure and nanocomposite materials, such as sol gel 5 , 6 hydrothermal 12 , Co 2 laser vaporization 2 , physical vapro deposition(PVD) 13 ….etc. The sol gel technique has been most used because it allows for low temperature synthesis, with excellent purity and simple control of the reaction conditions 6 .…”