Films of supersaturated Cd x Pb1–x S solid solutions: Composition prognostication, chemical synthesis, microstructure

Morphological and structural features of the CdxPb1−xS films obtained by CBD from ethylenediamine-citrate bath

“…To determine the CBD optimal conditions, analysis of ionic equilibria was carried out in the system «Pb(CH 3 COO) 2  CdCl 2  Na 3 C 6 H 5 O 7  (NH 3 ) 2 (CH 2 ) 2  N 2 H 4 CS» according to the method proposed in [26]. These calculations allowed estimating the formation regions of the main phases (PbS and CdS) and impurities (Cd(OH) 2 , Pb(OH) 2 ).…”

“…The rate decreasing is achieved by reducing its active concentration due to the metal ions binding into complex compounds. In the studied system lead ions form complexes with citrate ions Pb(Cit) − (instability constant, The regions of individual lead and cadmium sulfides formation, as well as their co-deposition region, were found as a graphical solution of the equilibrium conditions equation in the coordinates "the of the initial metal salt concentration power pC in -the ligand concentration [Na 3 Cit(En)] -pH" at 298 K [26]: [27]); pα M 2+ is the power of the fraction of free lead or cadmium ions in uncomplexed forms. The calculation was carried out considering all possible lead and cadmium forms according to the method proposed in [26].…”

“…where р is the power (negative logarithm); in is the lead or cadmium salt initial concentration; pSP MS , pSP M(OH) 2 are the solubility products' powers of sulfides CdS (pSP CdS = 26.6) and PbS (pSP PbS = 27.8) and hydroxides Cd(OH) 2 (pSP Cd(OH) 2 = 15.8) and Pb(OH) 2 (pSP Pb(OH) 2 = 13.66)[19], respectively; [CS(NH 2 ) 2 ] in is the thiocarbamide initial concentration in solution, equal to 0.6 mol/l; σ is the specific surface energy of metal sulfide (σ PbS = 1.2 J/m 2 and σ СdS = 0.9 J/m ; V m is the molar volume of the synthesized phase V m(PbS) = 31.9•10 -6 m 3 /mol and V m(CdS) = 29.97•10 -6 m 3 /mol; r cr is the critical nucleus radius (3.5•10 −9 m)[26]; R is the ideal gas constant, J/(mol•K); Т is the temperature of the…”