Lead selenide (PbSe) emerged 70+ years ago for its unique photoconductive sensitivity to the mid-wave infrared (MWIR) spectrum; however, new and exciting research continues to ignite interest in this material to this day. PbSe has endured primarily due to its high IR responsivity at room temperature (uncooled), large-area application space, and low-cost fabrication. PbSe has a large nominal Bohr exciton radius (∼46 nm) that allows bandgap tuning from 0.27 eV to as far as 2.0 eV by manipulation of grain size and morphology. This review aims to summarize the most recent state-of-the-art progress in PbSe photoconductivity research, including synthesized quantum-dots (QDs) and novel manufacturing methods.

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Photoconductive PbSe thin films for infrared imaging

Composition, structure and functional properties of nanostructured PbSe films deposited using different antioxidants

Enhancement of physical properties of nebulizer spray-pyrolyzed PbS thin films for Optoelectronic device application: an effect of Ag doping

Comparative experimental data, using dynamic light scattering methods, scanning electron and atomic force microscopy, on the composition, crystal structure, semiconductor and photoelectric properties of PbSe films deposited at the presence of sodium sulfite Na2SO3 and “sodium sulfite–ascorbic acid” complex antioxidant additive are presented. Significant changes in morphology, elemental and phase composition, the period of the crystal lattice of PbSe films been synthesized in the presence of Na2SO3 and Na2SO3 + C6H8O6 anti-oxidants before and after their thermoactivation at 653 K are found. It is shown that the introduction of a complex additive in comparison with Na2SO3 increases the homogeneity of the particles forming the layer, decreases the microstresses in it, reduces the value of thermal band gap from 0.349 to 0.308 eV, and increases the volt-watt sensitivity of the films by 28–30%.

Effect of “Sodium Sulfite–Ascorbic Acid” Complex Antioxidant Additive on the Composition, Structure and Semiconducting Properties of PbSe Film

Data on the kinetics and mechanism of the formation of a solid phase during the hydrochemical deposition of lead selenide films with inhibitors of selenocarbamide oxidation (sodium sulfite, ascorbic acid, and tin chloride) are systematized and analyzed. The effective rate constants of the conversion of a lead salt to selenide and the thickness of PbSe films are shown to depend on the nature and concentrations of the inhibiting additives. The effect of the nature of the inhibitors on the mechanism of nucleation is studied via dynamic light scattering. The stronger inhibiting effect of the simultaneous presence of sodium sulfite and ascorbic acid in the reaction mixture had on the process of selenocarbamide oxidation is confirmed.

Kinetics and Mechanism of the Formation of the Solid Phase during the Deposition of PbSe Films Using Inhibitors of Selenocarbamide Oxidation

Spectrophotometric method was used to study the kinetics of the process in which aqueous solutions of selenurea of various compositions are oxidized. Significant differences between the stabilities of selenurea solutions were revealed in relation to the selenurea concentration and also to the acidity, or alkalinity of a medium. It was shown that the stability of selenurea solutions is affected by additives of various antioxidants: sodium sulfite Na2SO3, ascorbic acid C6H8O6, hydroxylamine chloride NH2OH·HCl, hydrazine hydrate N2H4·H2O, and tin chloride SnCl2·2H2O. It was found that using a 1 : 1 mixture of antioxidants Na2SO3 and C6H8O6 substantially raises their antioxidant activity and stabilizes the aqueous solutions of selenurea during up to five days. A hydro-chemical precipitation in the acetate—ethylenediamine reaction system in the presence of the antioxidants under study was used to obtain lead selenide films of stoichiometric composition with thicknesses of 230‒670 nm. With the Na2SO3 + C6H8O6, Na2SO3, C6H8O6, and SnCl2 antioxidants used to stabilize selenurea solutions, a tendency is observed toward a decrease in the lattice constants of PbSe films from 6.1531 ± 0.0003 to 6.1367 ± 0.0002 A, an increase in the share of nanosize particles, and rise in the PbSe energy gap width from 0.78 to 1.0 e V.

Effect of Antioxidants on Stability of Aqueous Solutions of Selenurea and on Properties of Lead Selenide Films Obtained with These Antioxidants

Chemical deposition is used to obtain thin solid films of lead sulfide Pb(S, O) with oxygen contents of 0.2 to 30.7 at %, regulated by a variety of ligands. The oxygen effect on the mechanism of formation and optical properties of Pb(S, O) films is studied experimentally and through quantum-chemical modeling. A heterostructured nature of the synthesized Pb(S, O) compounds is shown for the first time, and a mechanism of their formation in an aqueous solution is proposed.

V. G. Bamburov

Papers

Effect of Antioxidants on Stability of Aqueous Solutions of Selenurea and on Properties of Lead Selenide Films Obtained with These Antioxidants

Nanostructured Pb(S, O) Films: Synthesis, Mechanism of Deposition, and Optical Properties