Electrochemical Modulation of the Photophysics of Surface-Localized Trap States in Core/Shell/(Shell) Quantum Dot Films.
Journal
Chemistry of materials : a publication of the American Chemical Society
ISSN: 0897-4756
Titre abrégé: Chem Mater
Pays: United States
ID NLM: 9884133
Informations de publication
Date de publication:
22 Oct 2019
22 Oct 2019
Historique:
received:
22
07
2019
revised:
23
09
2019
entrez:
1
11
2019
pubmed:
2
11
2019
medline:
2
11
2019
Statut:
ppublish
Résumé
In this work, we systematically study the spectroelectrochemical response of CdSe quantum dots (QDs), CdSe/CdS core/shell QDs with varying CdS shell thicknesses, and CdSe/CdS/ZnS core/shell/shell QDs in order to elucidate the influence of localized surface trap states on the optoelectronic properties. By correlating the differential absorbance and the photoluminescence upon electrochemically raising the Fermi level, we reveal that trap states near the conduction band (CB) edge give rise to nonradiative recombination pathways regardless of the CdS shell thickness, evidenced by quenching of the photoluminescence before the CB edge is populated with electrons. This points in the direction of shallow trap states localized on the CdS shell surface that give rise to nonradiative recombination pathways. We suggest that these shallow trap states reduce the quantum yield because of enhanced hole trapping when the Fermi level is raised electrochemically. We show that these shallow trap states are removed when additional wide band gap ZnS shells are grown around the CdSe/CdS core/shell QDs.
Identifiants
pubmed: 31666761
doi: 10.1021/acs.chemmater.9b02908
pmc: PMC6814269
doi:
Types de publication
Journal Article
Langues
eng
Pagination
8484-8493Informations de copyright
Copyright © 2019 American Chemical Society.
Déclaration de conflit d'intérêts
The authors declare no competing financial interest.
Références
Chem Mater. 2019 Jun 25;31(12):4575-4583
pubmed: 31274957
Nano Lett. 2014 Feb 12;14(2):486-94
pubmed: 24328946
J Phys Chem Lett. 2013 Mar 21;4(6):987-92
pubmed: 26291365
Nano Lett. 2005 Dec;5(12):2360-4
pubmed: 16351178
Nano Lett. 2015 Jun 10;15(6):3953-8
pubmed: 25990468
Nano Lett. 2017 Sep 13;17(9):5607-5613
pubmed: 28776995
J Am Chem Soc. 2018 May 2;140(17):5755-5763
pubmed: 29569443
ACS Nano. 2016 Jul 26;10(7):6877-87
pubmed: 27276033
Phys Rev Lett. 2011 May 6;106(18):187401
pubmed: 21635124
ACS Nano. 2013 Mar 26;7(3):2500-8
pubmed: 23398747
Chem Mater. 2018 Nov 13;30(21):8052-8061
pubmed: 30487664
J Am Chem Soc. 2018 May 30;140(21):6582-6590
pubmed: 29718666
Nano Lett. 2011 Feb 9;11(2):687-93
pubmed: 21207930
Nano Lett. 2007 Oct;7(10):2942-50
pubmed: 17845067
Nanoscale. 2018 Feb 15;10(7):3089-3111
pubmed: 29379916
ACS Nano. 2008 Apr;2(4):669-76
pubmed: 19206597
Nano Lett. 2013 Oct 9;13(10):4884-92
pubmed: 24010869
Nano Lett. 2015 May 13;15(5):3056-66
pubmed: 25853555
ACS Nano. 2013 Sep 24;7(9):7913-30
pubmed: 23941394
Nano Lett. 2014 Jan 8;14(1):353-8
pubmed: 24328385
Science. 2019 Mar 15;363(6432):1199-1202
pubmed: 30872520
J Am Chem Soc. 2017 Mar 8;139(9):3302-3311
pubmed: 28170239
ACS Nano. 2015 Nov 24;9(11):11430-8
pubmed: 26449673
ACS Nano. 2018 Jan 23;12(1):718-728
pubmed: 29286633
ACS Nano. 2017 Oct 24;11(10):10430-10438
pubmed: 28915009
Nat Nanotechnol. 2013 Mar;8(3):206-12
pubmed: 23396313
ACS Nano. 2016 Mar 22;10(3):3295-301
pubmed: 26885562
Nat Nanotechnol. 2014 Nov;9(11):891-5
pubmed: 25282045
ACS Nano. 2018 Nov 27;12(11):11244-11253
pubmed: 30372029
ACS Nano. 2015 Oct 27;9(10):10366-76
pubmed: 26389562
J Am Chem Soc. 2012 Mar 28;134(12):5484-7
pubmed: 22420898
J Am Chem Soc. 2018 Nov 21;140(46):15712-15723
pubmed: 30375226
Chem Rev. 2010 Jan;110(1):389-458
pubmed: 19958036
Nano Lett. 2014 Jul 9;14(7):3855-63
pubmed: 24914746
Nat Mater. 2013 May;12(5):445-51
pubmed: 23377294
J Am Chem Soc. 2003 Oct 15;125(41):12567-75
pubmed: 14531702
J Am Chem Soc. 2017 Sep 20;139(37):13208-13217
pubmed: 28841295
J Am Chem Soc. 2017 Apr 5;139(13):4866-4878
pubmed: 28292175
Chem Soc Rev. 2011 Mar;40(3):1512-46
pubmed: 20972490
Nature. 2000 Oct 26;407(6807):981-3
pubmed: 11069172
J Am Chem Soc. 2017 Nov 22;139(46):16556-16567
pubmed: 29094943
Nano Lett. 2017 Sep 13;17(9):5238-5243
pubmed: 28805396
J Am Chem Soc. 2016 Jul 6;138(26):8134-42
pubmed: 27312799
Nano Lett. 2018 Feb 14;18(2):1028-1034
pubmed: 29283266
Nano Lett. 2015 Nov 11;15(11):7718-25
pubmed: 26496661
J Am Chem Soc. 2008 Apr 16;130(15):5026-7
pubmed: 18355011
ACS Nano. 2017 Apr 25;11(4):4165-4173
pubmed: 28314094
Nano Lett. 2013 Apr 10;13(4):1810-5
pubmed: 23464673