Facile microwave-assisted synthesis of Al:Mn co-doped PbI₂ nanosheets: structural, vibrational, morphological, dielectric and radiation activity studies

Abstract

Herein, we report a successful development of nano-scale pure and Al and Mn co-doped PbI2 using facile microwaveassisted route. Structural study was done through X-ray diffraction analysis of grain size, dislocation density and lattice strain. The crystallite size was found to vary from 28 nm to 40 nm due to Al:Mn co-doping in PbI2. The presence of various vibrational modes was confirmed by FT-IR spectroscopy and red shifting was observed in peak positions compared to the bulk. Surface morphology, examined using a scanning electron microscope, confirmed the formation of single crystal nanosheets of a thickness in the range of 10 nm to 30 nm. The single crystal nanosheets were found to be transformed to large area nanosheets due to the doping. Enhancement in dielectric constant from ~7.5 to 11 was observed with increasing Al doping concentration. Linear attenuation coefficient was calculated and showed the enhancement of blocking gamma rays with increasing doping concentration. Its value was found to increase from 7.5 to 12.8 with the doping. The results suggest that the synthesized nanostructures can be used for detection and absorption of gamma rays emitted by 137Cs and 241Am sources.

Microwave-assisted synthesis of Mg:PbI2nanostructures and their structural, morphological, optical, dielectric and electrical properties for optoelectronic technology

“…The effects of different element doping concentrations on PbI 2 nanostructures have been reported earlier by various researchers. [14,23,24,39] The crystal size of nanostructures was obtained using Debye Scherer's empirical relation D 101 = kλ /β cos θ , and crystallite sizes were in order of 47-51 nm. Lattice constants, dislocation density and strain of nanostructures were estimated experimentally from the following wellknown relations: [40][41][42] 1…”