The order–disorder transition of kesterite (CZTS, Cu2ZnSnS4) from I4̅ to I4̅2m crystal structures has a marked effect on Seebeck coefficient, which displays a sharp enhancement at the transition temperature, around 533 K. Considered to be detrimental for the performance of photovoltaic kesterite, the order–disorder transition appears to be beneficial for thermopower. Experimental data and ab initio calculations explain the origin of this enhancement: the increase of crystal symmetry in the disordered polymorph leads to a favorable electronic band structure characterized by flat and converged bands. At the transition, a sharp drop in mobility and increase in carrier concentration experimentally prove this mechanism of Seebeck enhancement. This, other than providing a new understanding of the material, can cast light on some profitable mechanisms to enhance the thermoelectric performance. Additionally, the increase in Seebeck provides an efficient tool to observe the transition and possibly to quantify disorder.

Order–Disorder Transition in Kesterite Cu2ZnSnS4: Thermopower Enhancement via Electronic Band Structure Modification / Isotta, Eleonora; Mukherjee, Binayak; Fanciulli, Carlo; Pugno, Nicola M.; Scardi, Paolo. - In: JOURNAL OF PHYSICAL CHEMISTRY. C. - ISSN 1932-7447. - STAMPA. - 124:13(2020), pp. 7091-7096. [10.1021/acs.jpcc.0c00886]

Order–Disorder Transition in Kesterite Cu2ZnSnS4: Thermopower Enhancement via Electronic Band Structure Modification

Isotta, Eleonora;Pugno, Nicola M.;Scardi, Paolo
2020-01-01

Abstract

The order–disorder transition of kesterite (CZTS, Cu2ZnSnS4) from I4̅ to I4̅2m crystal structures has a marked effect on Seebeck coefficient, which displays a sharp enhancement at the transition temperature, around 533 K. Considered to be detrimental for the performance of photovoltaic kesterite, the order–disorder transition appears to be beneficial for thermopower. Experimental data and ab initio calculations explain the origin of this enhancement: the increase of crystal symmetry in the disordered polymorph leads to a favorable electronic band structure characterized by flat and converged bands. At the transition, a sharp drop in mobility and increase in carrier concentration experimentally prove this mechanism of Seebeck enhancement. This, other than providing a new understanding of the material, can cast light on some profitable mechanisms to enhance the thermoelectric performance. Additionally, the increase in Seebeck provides an efficient tool to observe the transition and possibly to quantify disorder.
2020
13
Isotta, Eleonora; Mukherjee, Binayak; Fanciulli, Carlo; Pugno, Nicola M.; Scardi, Paolo
Order–Disorder Transition in Kesterite Cu2ZnSnS4: Thermopower Enhancement via Electronic Band Structure Modification / Isotta, Eleonora; Mukherjee, Binayak; Fanciulli, Carlo; Pugno, Nicola M.; Scardi, Paolo. - In: JOURNAL OF PHYSICAL CHEMISTRY. C. - ISSN 1932-7447. - STAMPA. - 124:13(2020), pp. 7091-7096. [10.1021/acs.jpcc.0c00886]
File in questo prodotto:
File Dimensione Formato  
acs.jpcc.0c00886.pdf

Solo gestori archivio

Descrizione: Versione editoriale finale
Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 1.7 MB
Formato Adobe PDF
1.7 MB Adobe PDF   Visualizza/Apri
jp0c00886_si_001.pdf

Solo gestori archivio

Tipologia: Altro materiale allegato (Other attachments)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 392.63 kB
Formato Adobe PDF
392.63 kB Adobe PDF   Visualizza/Apri
Isotta-2020-Order-disorder-transition-in-kester_2.pdf

Open Access dal 10/03/2021

Tipologia: Post-print referato (Refereed author’s manuscript)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 3.47 MB
Formato Adobe PDF
3.47 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/255277
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 31
  • ???jsp.display-item.citation.isi??? 29
social impact