Electronic structure and defect states in bismuth and antimony sulphides identified by energy-resolved electrochemical impedance spectroscopy

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21230%2F25%3A00383402" target="_blank" >RIV/68407700:21230/25:00383402 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1088/2515-7655/add59f" target="_blank" >https://doi.org/10.1088/2515-7655/add59f</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/2515-7655/add59f" target="_blank" >10.1088/2515-7655/add59f</a>

Result language

angličtina

Original language name

Electronic structure and defect states in bismuth and antimony sulphides identified by energy-resolved electrochemical impedance spectroscopy

Original language description

One of the reasons chalcogenide-based photovoltaic solar cells do not yet meet the expected high-power conversion efficiencies is a lack of understanding of their electronic structure, and particularly the nature of the point defects in the absorber materials. We show that the density of states (DOS) of the characteristic features of the electronic structure, such as band edges and energy distribution of defects, can be obtained experimentally by energy-resolved electrochemical impedance spectroscopy (ER-EIS) in a technically simple and quick way. The ER-EIS data correlate well with theoretical density functional theory (DFT) calculations. The ER-EIS reveals that Bi2S3, has only shallow defects near the conduction band minimum (CBM). In Sb2S3, ER-EIS also shows deep defect states, which can be the cause of the low electrical conductivity of Sb2S3 and lower than theoretically possible power conversion efficiency of Sb2S3-based solar cells. A dominant sulphur vacancy defect was identified in Bi- and Sb-chalcogenides. In the (SbxBi(1-x))2S3 ternary alloy series, a gradual transformation of CBM and defect states in the band gap was observed. Notably, a 1:9 ratio of Bi:Sb cations already transforms the deep sulphur defects into shallow ones while keeping the band edges similar to those of the pristine Sb2S3. It can provide a novel strategy for healing the deep defect states in Sb2S3, a crucial step for boosting solar cell performance.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project

<a href="/en/project/EH22_008%2F0004617" target="_blank" >EH22_008/0004617: Energy conversion and storage</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Physics: Energy

ISSN

2515-7655

e-ISSN

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Volume of the periodical

7

Issue of the periodical within the volume

3

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

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UT code for WoS article

001493166000001

EID of the result in the Scopus database

2-s2.0-105006721785