Structural Features of PbS Nanocube Monolayers upon Treatment with Mono- and Dicarboxylic Acids and Thiols at a Liquid-Air Interface

Martin R. McPhail, Gavin P. Campbell, Michael J. Bedzyk, Emily A Weiss

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

This paper describes the ordering of PbS nanocubes (NCs) within free-standing monolayers (suspended on acetonitrile), upon exchanging the native oleate ligands for a series of thiolate and carboxylate ligands at the liquid-air interface. Treatment with either carboxylic acids or thiols effectively decreases the inter-NC separation of nearest-neighbor particles without etching the NC surface. Dicarboxylic acids and dithiols bridge neighboring NCs with an interparticle separation that is consistent with fully extended, bridging ligands. Monocarboxylic acids and monothiols separate NCs by an amount governed by their length, with long-chain ligands showing significant intercalation. 1H NMR spectroscopy shows carboxylic acids are more effective at replacing the native oleate than are thiols, which we ascribe to the lower pKa values of carboxylic acids. The fast exchange that occurs upon treatment with monocarboxylic acids kinetically traps the clusters of particles in nonclosed packed geometries, so monolayers treated with monocarboxylic acids are, on average, less ordered than those treated with monothiols. Ex situ electron microscopy and grazing incidence small-angle X-ray scattering (GISAXS) analyses of deposited films on Si/SiO2 substrates show that NCs exchanged with nonbridging ligands pack more efficiently at long length scales than do NCs exchanged with bridging ligands, due primarily to the creation of defects within the NC lattice in response to the rigidity of the bridging ligand.

Original languageEnglish
Pages (from-to)6666-6673
Number of pages8
JournalLangmuir
Volume32
Issue number26
DOIs
Publication statusPublished - Jul 5 2016

Fingerprint

Dicarboxylic Acids
liquid air
dicarboxylic acids
Sulfhydryl Compounds
thiols
Monolayers
Ligands
ligands
Acids
Liquids
Air
Carboxylic Acids
Carboxylic acids
carboxylic acids
Oleic Acid
acids
exchanging
Intercalation
Acetonitrile
X ray scattering

ASJC Scopus subject areas

  • Electrochemistry
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Materials Science(all)
  • Spectroscopy

Cite this

Structural Features of PbS Nanocube Monolayers upon Treatment with Mono- and Dicarboxylic Acids and Thiols at a Liquid-Air Interface. / McPhail, Martin R.; Campbell, Gavin P.; Bedzyk, Michael J.; Weiss, Emily A.

In: Langmuir, Vol. 32, No. 26, 05.07.2016, p. 6666-6673.

Research output: Contribution to journalArticle

McPhail, Martin R. ; Campbell, Gavin P. ; Bedzyk, Michael J. ; Weiss, Emily A. / Structural Features of PbS Nanocube Monolayers upon Treatment with Mono- and Dicarboxylic Acids and Thiols at a Liquid-Air Interface. In: Langmuir. 2016 ; Vol. 32, No. 26. pp. 6666-6673.
@article{bae2e7db86e34ca790a9a10fc32648ac,
title = "Structural Features of PbS Nanocube Monolayers upon Treatment with Mono- and Dicarboxylic Acids and Thiols at a Liquid-Air Interface",
abstract = "This paper describes the ordering of PbS nanocubes (NCs) within free-standing monolayers (suspended on acetonitrile), upon exchanging the native oleate ligands for a series of thiolate and carboxylate ligands at the liquid-air interface. Treatment with either carboxylic acids or thiols effectively decreases the inter-NC separation of nearest-neighbor particles without etching the NC surface. Dicarboxylic acids and dithiols bridge neighboring NCs with an interparticle separation that is consistent with fully extended, bridging ligands. Monocarboxylic acids and monothiols separate NCs by an amount governed by their length, with long-chain ligands showing significant intercalation. 1H NMR spectroscopy shows carboxylic acids are more effective at replacing the native oleate than are thiols, which we ascribe to the lower pKa values of carboxylic acids. The fast exchange that occurs upon treatment with monocarboxylic acids kinetically traps the clusters of particles in nonclosed packed geometries, so monolayers treated with monocarboxylic acids are, on average, less ordered than those treated with monothiols. Ex situ electron microscopy and grazing incidence small-angle X-ray scattering (GISAXS) analyses of deposited films on Si/SiO2 substrates show that NCs exchanged with nonbridging ligands pack more efficiently at long length scales than do NCs exchanged with bridging ligands, due primarily to the creation of defects within the NC lattice in response to the rigidity of the bridging ligand.",
author = "McPhail, {Martin R.} and Campbell, {Gavin P.} and Bedzyk, {Michael J.} and Weiss, {Emily A}",
year = "2016",
month = "7",
day = "5",
doi = "10.1021/acs.langmuir.6b01444",
language = "English",
volume = "32",
pages = "6666--6673",
journal = "Langmuir",
issn = "0743-7463",
publisher = "American Chemical Society",
number = "26",

}

TY - JOUR

T1 - Structural Features of PbS Nanocube Monolayers upon Treatment with Mono- and Dicarboxylic Acids and Thiols at a Liquid-Air Interface

AU - McPhail, Martin R.

AU - Campbell, Gavin P.

AU - Bedzyk, Michael J.

AU - Weiss, Emily A

PY - 2016/7/5

Y1 - 2016/7/5

N2 - This paper describes the ordering of PbS nanocubes (NCs) within free-standing monolayers (suspended on acetonitrile), upon exchanging the native oleate ligands for a series of thiolate and carboxylate ligands at the liquid-air interface. Treatment with either carboxylic acids or thiols effectively decreases the inter-NC separation of nearest-neighbor particles without etching the NC surface. Dicarboxylic acids and dithiols bridge neighboring NCs with an interparticle separation that is consistent with fully extended, bridging ligands. Monocarboxylic acids and monothiols separate NCs by an amount governed by their length, with long-chain ligands showing significant intercalation. 1H NMR spectroscopy shows carboxylic acids are more effective at replacing the native oleate than are thiols, which we ascribe to the lower pKa values of carboxylic acids. The fast exchange that occurs upon treatment with monocarboxylic acids kinetically traps the clusters of particles in nonclosed packed geometries, so monolayers treated with monocarboxylic acids are, on average, less ordered than those treated with monothiols. Ex situ electron microscopy and grazing incidence small-angle X-ray scattering (GISAXS) analyses of deposited films on Si/SiO2 substrates show that NCs exchanged with nonbridging ligands pack more efficiently at long length scales than do NCs exchanged with bridging ligands, due primarily to the creation of defects within the NC lattice in response to the rigidity of the bridging ligand.

AB - This paper describes the ordering of PbS nanocubes (NCs) within free-standing monolayers (suspended on acetonitrile), upon exchanging the native oleate ligands for a series of thiolate and carboxylate ligands at the liquid-air interface. Treatment with either carboxylic acids or thiols effectively decreases the inter-NC separation of nearest-neighbor particles without etching the NC surface. Dicarboxylic acids and dithiols bridge neighboring NCs with an interparticle separation that is consistent with fully extended, bridging ligands. Monocarboxylic acids and monothiols separate NCs by an amount governed by their length, with long-chain ligands showing significant intercalation. 1H NMR spectroscopy shows carboxylic acids are more effective at replacing the native oleate than are thiols, which we ascribe to the lower pKa values of carboxylic acids. The fast exchange that occurs upon treatment with monocarboxylic acids kinetically traps the clusters of particles in nonclosed packed geometries, so monolayers treated with monocarboxylic acids are, on average, less ordered than those treated with monothiols. Ex situ electron microscopy and grazing incidence small-angle X-ray scattering (GISAXS) analyses of deposited films on Si/SiO2 substrates show that NCs exchanged with nonbridging ligands pack more efficiently at long length scales than do NCs exchanged with bridging ligands, due primarily to the creation of defects within the NC lattice in response to the rigidity of the bridging ligand.

UR - http://www.scopus.com/inward/record.url?scp=84978077208&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84978077208&partnerID=8YFLogxK

U2 - 10.1021/acs.langmuir.6b01444

DO - 10.1021/acs.langmuir.6b01444

M3 - Article

VL - 32

SP - 6666

EP - 6673

JO - Langmuir

JF - Langmuir

SN - 0743-7463

IS - 26

ER -