Defect Characterization in Cu<sub>2</sub>NiX (X = SSe, Te<sub>2</sub>, SeTe) Chalcogenide Semiconductors Using Positron Annihilation Spectroscopy

Samadov S. F., Guliyeva K. M., Sidorin A. A., Trung N. V. M., Aliyev Y., Orlov O. S., ...More

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, vol.51, no.2, pp.2137-2147, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 51 Issue: 2
  • Publication Date: 2026
  • Doi Number: 10.1007/s13369-025-10262-2
  • Journal Name: ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, zbMATH
  • Page Numbers: pp.2137-2147
  • Azerbaijan State University of Economics (UNEC) Affiliated: No

Abstract

We have been studying the structural and defect properties of Cu2NiX (X = SSe, Te2, SeTe) chalcogenide semiconductors synthesized by the Bridgman-Stockbarger method using positron annihilation lifetime spectroscopy (PALS) and Doppler broadening annihilation spectroscopy (DBAS). These methods let us study defect configurations in great detail. These configurations include vacancies, clusters, and interstitials, which are affected by atomic radii and bonding properties. PALS measurements show variations in defect types and concentrations among the samples. This helps us identify three distinct lifetime components (tau 1, tau 2, tau 3) and their corresponding intensities. We found that Cu2NiTe2 had the highest tau(2) (288 ps) and pore volume (0.056 nm3). DBAS measurements showed that the Cu2NiTe2 compound had the highest defect concentration. DBAS gave us some great insights into the electron momentum distribution and showed us the role of chalcogen substitution in defect evolution. All of these findings show how well Cu2NiX materials can be used to optimize their structural properties for optoelectronic and energy applications.