Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: lead telluride

Sortuj według:

Ogranicz wyniki do:

Electrochemical Studies of Lead Telluride Behavior in Acidic Nitrate Solutions

Rudnik E., Biskup P.

Archives of Metallurgy and Materials

2015

Vol. 60, iss. 1

95--100

Electrochemistry of lead telluride stationary electrode was studied in nitric acid solutions of pH 1.5-3.0. E-pH diagram for Pb-Te-H2O system was calculated. Results of cyclic voltammetry of Pb, Te and PbTe were discussed in correlation with thermodynamic predictions. Anodic dissolution of PbTe electrode at potential approx. -100÷50 mV (SCE) resulted in tellurium formation, while above 300 mV TeO2 was mainly produced. The latter could dissolve to HTeO+2 under acidic electrolyte, but it was inhibited by increased pH of the bath.

Przeprowadzono elektrochemiczne badania zachowania się tellurku ołowiu w roztworach kwasu azotowego(V) o pH 1,5-3,0. Obliczono diagram równowagi E-pH dla układu Pb-Te-H2O. Przedyskutowano wyniki pomiarów woltamperometrii cyklicznej Pb, Te i PbTe w odniesieniu do przewidywań termodynamicznych. Produktem utleniania tellurku ołowiu przy potencjałach ok. -100÷50 mV (NEK) jest tellur, natomiast powyżej 300 mV tworzy się przede wszystkim 2, który ulega wtórnemu rozpuszczaniu w roztworze kwaśnym z utworzeniem HTeO+2. Proces jest hamowany przez wzrost pH elektrolitu.

Nature of gallium deep centres in lead telluride based semiconductors

Petrenko T. L., Plyatsko S. V.

Opto-Electronics Review

2010

Vol. 18, No. 3

310-317

Doped with Ga lead telluride was taken as a model object to explain the nature of group-III deep levels in IV-VI semiconductors and to elucidate the vapour phase doping mechanism. For this goal, interaction of various gallium-containing molecules with defect-free crystal as well as with native defects in PbTe was considered. Formation energies for different point defects created in PbTe as a result of interaction the Ga2Te molecules, Ga2 dimers and single Ga atoms with a host crystal were calculated using density functional theory. Particularly GaPb and Gai together with formation of accompanied self interstitials Pbi in various charge states were examined. In addition we propose the new type of defects - the impurity complex (2Ga)Pb which looks like <111>-oriented gallium dumbbell. Calculations suggest the double donor behaviour and DX-like properties of this defect together with extremely low formation energy values. Namely, (2Ga)Pb centres are preferably formed under Ga2Te doping while (Ga2)Pb+Pbi ones are formed under Ga2 or Ga doping. In all cases, formation energies are negative and resulting defect concentration is determined by reaction kinetics only. Mechanisms of the lead vacancy compensation with the vapour phase doping are considered as well.