Detection and identification of vacancy defects in antimony selenide

TY - JOUR

T1 - Detection and identification of vacancy defects in antimony selenide

AU - Keeble, David J.

AU - Hobson, Theodore D. C.

AU - Wiktor, Julia

AU - Berger, Ethan

AU - Dickmann, Marcel

AU - Elsharkawy, Mohamed R. M.

AU - Egger, Werner

AU - Major, Jonathan D.

AU - Durose, Ken

N1 - © The Author(s) 2025.

PY - 2026/1/3

Y1 - 2026/1/3

N2 - Antimony selenide (Sb2Se3) has an optimal bandgap and absorption coefficient for thin film solar cell applications and comprises earth abundant elements. The rate of increase in reported power conversion efficiencies has slowed due to a persistently large open circuit voltage deficit attributed to detrimental concentrations of point defects. Here we use depth-profiling positron annihilation lifetime spectroscopy to study Sb2Se3 crystals and thin films. The method is specific to neutral and negative charge states of vacancy-related defects. Both monovacancy and divacancy defects are identified in intrinsic and n-type samples but no monovacancy defects are detected in the p-type sample. Comparison of the experimental positron lifetimes with density functional theory calculated values provide evidence for the observation of Sb monovacancies in the –3 state and of Se monovacancies in the –2 state. The results are consistent with recent density function theory predictions that the Sb and the Se monovacancy defects both have accessible negative charge states.

AB - Antimony selenide (Sb2Se3) has an optimal bandgap and absorption coefficient for thin film solar cell applications and comprises earth abundant elements. The rate of increase in reported power conversion efficiencies has slowed due to a persistently large open circuit voltage deficit attributed to detrimental concentrations of point defects. Here we use depth-profiling positron annihilation lifetime spectroscopy to study Sb2Se3 crystals and thin films. The method is specific to neutral and negative charge states of vacancy-related defects. Both monovacancy and divacancy defects are identified in intrinsic and n-type samples but no monovacancy defects are detected in the p-type sample. Comparison of the experimental positron lifetimes with density functional theory calculated values provide evidence for the observation of Sb monovacancies in the –3 state and of Se monovacancies in the –2 state. The results are consistent with recent density function theory predictions that the Sb and the Se monovacancy defects both have accessible negative charge states.

U2 - 10.1038/S41467-025-68153-X

DO - 10.1038/S41467-025-68153-X

M3 - Article

SN - 2041-1723

VL - 17

SP - 1

EP - 9

JO - Nature Communications

JF - Nature Communications

IS - 1

M1 - 1413

ER -