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

Kód výsledku v 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>

Výsledek na webu

<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>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

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

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

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

Projekt

<a href="/cs/project/EH22_008%2F0004617" target="_blank" >EH22_008/0004617: Konverze a skladování energie</a><br>

Návaznosti

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

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Journal of Physics: Energy

ISSN

2515-7655

e-ISSN

—

Svazek periodika

7

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

—

Kód UT WoS článku

001493166000001

EID výsledku v databázi Scopus

2-s2.0-105006721785