![]() ![]() Moreover, the sample preparation process in hydrothermal method enables the simple growth of high-quality, dense, and perpendicularly oriented one-dimensional nanostructure over a large area. This technique also requires low temperature (may be useful for in-situ doping during the synthesis of ZnO NRs) and has easy control of deposition parameters and simple deposition set-up. Nevertheless, hydrothermal technique is versatile, safe, and low cost with the use of water as a reaction medium. The above methods usually require complex synthesis setup or high temperature and harmful solvents. ![]() Various techniques, such as pulse laser deposition, radio frequency (RF) reactive magnetron sputtering, electrospinning, sol–gel spin coating, and spray pyrolysis, have been used for the growth of Mg-doped ZnO nanostructures. ![]() However, the growth of single crystal Mg-doped ZnO NRs has been reported to be difficult because of phase separation after certain Mg doping content. One-dimensional nanostructured Mg-doped ZnO with various morphologies, such as NRs, nanowires (NWs), nanofibers (NFs), and nanobelts (NBs), have been fabricated, ,. Mg-doped ZnO nanostructures showed remarkable optical and electronic properties and have been proposed for numerous applications, such as light-emitting diodes, , UV lasers, UV light sensors, , solar cells, , gas sensors, ,, , and photo catalysts. Among them, Mg has been identified as an attractive doping element because of the similarity of the ionic radius of Mg 2+ (0.057 nm) with Zn 2+ (0.060 nm), which means that replacing Zn with Mg will not induce any phase transformation or even lattice distortion, and consequently reduce or eliminate the formation of native defects causing from nonstoichiometric property of ZnO nanostructure. A number of elements, such as Cd, Cu, Fe, Er, Mg, and Mn, have been used to dope ZnO, ,,. ĭoping or alloying of ZnO has gained significant interest because of the ability to tune the energy band gap from ultraviolet to visible wavelengths, depending on the nature of the doping and its concentration. To achieve the considerable advantages of ZnO, its structural, electrical, and optical properties should be tuned, which is important for practical applications band gap modulation is a promising candidate for such tuning. Furthermore, ZnO possesses many advantages, including inexpensiveness and availability, easy production procedure, high thermal and chemical stability at moderately high temperatures, and non-toxicity. With its wide direct band gap (3.37 eV) and large exaction binding energy (60 meV), ZnO is particularly an attractive emitter in the violet and blue regions. ZnO nanorods (NRs) are attracting the attention of many researchers because of their unique and enhanced properties thereby offering numerous potential applications in photonic, optoelectronic, spintronic, and piezoelectric devices,. The as-obtained results highlight the effectiveness of deposition temperature on Mg-doped ZnO NRs as an active layer during the fabrication of UV-LED device. The electroluminescence (EL) spectra under forward bias show that the diode emits a unique UV-light centered at 382 nm. The optimized tapering pyramidal-shaped Mg-doped ZnO NRs have also been grown onto p-GaN and the (ZnO:Mg NWs)/(p-GaN) heterojunction has been used to fabricate an LED device. X-ray diffraction analysis confirms the formation of pure single phase hexagonal (Wurtzite) structure while photoluminescence study shows a strong UV emission at 378 nm. At deposition temperature of 150 ☌ unidirectional tapering pyramidal-shaped Mg-doped ZnO NRs with high density was obtained, which is favorable for light-emitting diode (LED) application. Field-emission scanning electron microscopy observations reveal that both surface morphology and topography depend significantly on growth temperature. Single crystal Mg-doped ZnO nanorods (NRs) are successfully deposited onto ZnO-seeded Si substrate through a facile hydrothermal method using Zn and Mg nitrates as precursor and dopant, respectively. ![]()
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