[PDF]    http://dx.doi.org/10.3952/lithjphys.49209

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 49, 203–208 (2009)


ELECTRICAL CONDUCTIVITY, ELECTROCHEMICAL AND OPTICAL PROPERTIES OF Cu7GeS5I–Cu7GeSe5I SUPERIONIC SOLID SOLUTIONS
I.P. Studenyaka,V.V. Bilanchuka, O.P. Kokhana, Yu.M. Stasyuka, A.F. Orliukasb, A. Kežionisb, E. Kazakevičiusb, and T. Šalkusb
aUzhhorod National University, 46 Pidhirna St, 88000 Uzhhorod, Ukraine
bFaculty of Physics, Vilnius University, Saulėtekio 9, LT-10222 Vilnius, Lithuania
E-mail: studenyak@dr.com

Received 28 January 2009; accepted 18 June 2009

Single crystals of Cu7GeS5I–Cu7GeSe5I superionic solid solutions were grown by chemical transport. Their electrical conductivity in the frequency range 1.0\cdot106–1.2\cdot109 Hz and in the temperature range 100–300 K was measured; the compositional dependences of the electrical conductivity and activation energy were obtained. Electrochemical studies of Cu7GeS5I–Cu7GeSe5I solid solutions were performed, the character of compositional variation of the electrode potential and the range of the electrochemical stability at S\rightarrowSe substitution were determined. The optical absorption edge of Cu7GeS5I–Cu7GeSe5I superionic solid solutions in the temperature range 77–300 K were studied; the compositional dependences of the optical pseudogap and Urbach energy were obtained.
Keywords: superionic conductors, electrical conductivity, electrochemical properties, optical absorption edge
PACS: 72.80.Jc, 78.40.Ha


Cu7GeS5I–Cu7GeSe5I SUPERJONINIŲ KIETŲJŲ TIRPALŲ ELEKTRINIS LAIDUMAS BEI ELEKTROCHEMINĖS IR OPTINĖS SAVYBĖS
I.P. Studenyaka,V.V. Bilanchuka, O.P. Kokhana, Yu.M. Stasyuka, A.F. Orliukasb, A. Kežionisb, E. Kazakevičiusb, T. Šalkusb
aUžhorodo nacionalinis universitetas, Užhorodas, Ukraina
bPuslaidininkiu zikos institutas, Vilnius, Lietuva

Cu7GeS5I–Cu7GeSe5I superjoninių kietųjų tirpalų monokristalai buvo užauginti cheminės pernašos metodu. Jų elektrinis laidumas išmatuotas 1,0\cdot106–1,2\cdot109 Hz dažnių ir 100–300 K temperatūros intervaluose ir nustatytos elektrinio laidumo bei aktyvacijos energijos priklausmybės nuo cheminės sudėties parametro. Atlikti Cu7GeS5I–Cu7GeSe5I kietųjų tirpalų elektrocheminiai tyrimai, nustatyti elektrodų sudėties kitimo įtakos jų potencialui pobūdis ir elektrocheminio stabilumo sritis keičiant S\rightarrowSe. Cu7GeS5I–Cu7GeSe5I superjoninių kietųjų tirpalų optinė sugerties riba ištirta 77–300 K temperatūros intervale, nustatyta cheminės sudėties įtaka optiniam pseudotarpui ir Urbacho energijos vertei.


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