Microstructure, optical, dielectric and electrical characterizations of Mn doped ZnO nanocrystals synthesized by mechanical alloying

Design of Catalysts for Glycolysis of Polyethylene Terephthalate from Spent Batteries

“…[34] It is known that ZnO semiconductors present monovacancies in both sublattices, zinc vacancies (V Zn ) and oxygen vacancies (V O ) with different charge states and those generated by mechanical mill as oxygen interstitials (O i ) and zinc interstitials (Zn i ). [23,37] The presence of these different defect levels was also confirmed by positron annihilation lifetime spectroscopy (PALS) in similar semiconductor studies. [57] It seems that the preparation technique, and in consequence the kind of induced defects, is relevant for a correct and unique characterization of the optical properties.…”

“…Moreover, the involvement of vacancies on the structural, electronic, and magnetic properties on Mn‐doped ZnO was previously proposed by means of DFT + U calculations embodied in the VASP code [34] . It is known that ZnO semiconductors present monovacancies in both sublattices, zinc vacancies (V Zn ) and oxygen vacancies (V O ) with different charge states and those generated by mechanical mill as oxygen interstitials (O i ) and zinc interstitials (Zn i ) [23,37] . The presence of these different defect levels was also confirmed by positron annihilation lifetime spectroscopy (PALS) in similar semiconductor studies [57] .…”

“…One of the most chosen dopant atoms is manganese since its ionic radius is comparable with the ionic radius of Zn 2 + . Several methods were used to synthesize Mn doped ZnO like co-precipitation, [18][19][20] sol gel, [21] solid state reactions, [22] hydrothermal methods, [23,24] and chemical bath deposition, [25] in order to investigate the different properties of Mn/ZnO nanoparticles.…”

INVESTIGATION OF OXYGEN-RELATED DEFECTS IN ZnO: GROWING TIME AND Mn CONCENTRATION EFFECTS

“…Zinc oxide (ZnO) being which is an intrinsic n-type II-VI semiconductor and have a wide-band gap (3.37 eV) and a large exciton binding energy (60 meV, at room temperature) has received considerable attention since it is low cost, non-toxic, chemically stable, high thermally stable environmentally friendly and further its optical and electrical properties can be tuned by doping (Putri et al, 2018;Karmakar et al, 2012;Kadam et al, 2017;Dhara et al, 2018;Fan et al, 2004;Wang et al, 2011;Choudhury et al, 2016). Therefore, ZnO has several applications such as gas sensors (Wang et al, 2017;Wang et al, 2015;Othman et al, 2017), solar cells (Dhara et al, 2018;Sekine et al, 2009;Keis et al, 2002;Law et al, 2005;Martinson et al, 2007), and light emitting diodes (Saito et al, 2002), optical modulator waveguides (Koch et al, 1995), field effect transistor (Vijayalakshmi et al, 2015), UV detectors (Das et al, 2010), and surface acoustic wave filters (Emanetoglu et al, 1999). ZnO has been synthesized using different techniques such as microwave-assisted synthesis (Schneider et al, 2010), sol-gel processing (Bahnemann et al, 1987), hydrothermal synthesis (Li et al, 2001), aerosol spray analysis (Motaung et al, 2014), wet chemical (Toloman et al, 2013) and hydrolysis/condensation (Cohn et al, 2012).…”

FABRICATION of n-ZnO:Mn/p-Si HETEROJUNCTION DIODES and ITS I-V, C-V CHARACTERISTICS

“…ZnO is a suitable host material for Mn doped as it is appropriate to replace the Zn 2+ cations of Mn 2+ metal ions when considering the ionic diameters of Mn 2+ and Zn 2+ . Researchers have done some experimental studies on Mn-doped ZnO using physical and chemical methods [7][8][9]. These studies reported currently relate to the physical property of Mn-doped ZnO films but there are very few studies on the n-ZnO:Mn/p-Si heterojunction [3], [10].…”