Growth of mercuric iodide crystals

Abstract

Mercuric Iodide (HgI 2 ) is a semiconductor candidate for the construction of X-and gamma-ray detectors for digital medical imaging due to its high atomic number (Z Hg = 80, Z I = 53). Also, HgI 2 has a wide optical band-gap (2.13 eV) and high photon absorption coefficient for high-energy radiation. Different structures can lead to varying electrical and optical properties of the final material. In this work, HgI 2 crystals were produced by the solvent evaporation technique. The solvents used were ethanol (solubility around 20 mg/ml at 25 o C), ether (solubility around 3.5 mg/ml at 25 o C) and acetone (solubility around 24mg/ml at 25 o C). The evaporation conditions were varied in order to produce different final crystals. The Bérnard cells are responsible for crystallites formation due to the Bérnard-Maragoni convection in the liquid. Millimeter-sized crystals can be obtained as seen by Scanning Electron Microscopy.

Study the effect of gamma-ray irradiation on the optical properties of HgI2 thin film using method solvent evaporation

“…In spite of the excellent features of a singular crystal of HgI 2 , the technique used to produce single crystal is very expensive and more complicate in fabrication, the fabricating of singular crystal HgI 2 for an appropriate shape to be utilized in large range is not practice. Therefore using near singular crystal feature of poly crystalline HgI 2 films via physic vaporing transporting (PVT) [5] or by physic vaporing deposing (PVD) [6,7] with abundant great sensation that could be achieved for x-ray image, or via screen print [8,9] with much lower dark current but reduced sensitivity, and by solvent evaporating method that has by now been utilized to crystal growing [10,11]. The last technique is much cheaper and easier in fabricating HgI 2 films, since it has no need to vacuum systems.…”

“…The last technique is much cheaper and easier in fabricating HgI 2 films, since it has no need to vacuum systems. Such method requires the sol that is made up of HgI 2 powders and a volatile solvent whether ethanol, ether, acetone [10] or tetrahydroforane (THF) [11]. The solution is placed inside a clean beaker and after a complete solvent evaporation from the beaker HgI 2 films are deposited in the bottom of the beaker and the properties of the film depend on the evaporation rate.…”

A new nanocomposite superionic system (CdHgI4/HgI2): Synthesis, characterization and experimental investigation

“…In fact two crystalline forms of HgI 2 (α-and β-types) exist, the former red and the latter yellow. Different structures can lead to varying electrical and optical properties of the final material [14].…”