Abstract
Colloidal quantum dot (QD) photocatalysts have the electrochemical and optical properties to be highly effective for a range of redox reactions. QDs are proven photo-redox catalysts for a variety of reactions in organic solvents but are less prominent for aqueous reactions. Aqueous QD photocatalysts require hydrophilic ligand shells that provide long-term colloidal stability but are not so tight-binding as to prevent catalytic substrates from accessing the QD surface. Common thiolate ligands, which also poison many co-catalysts and undergo photo-oxidative desorption, are therefore often not an option. This paper describes a framework for the design of water-solubilizing ligands that are in dynamic exchange on and off the QD surface, but still provide long-term colloidal stability to CdS QDs. The binding affinity and inter-ligand electrostatic interactions of a bifunctional ligand, aminoethyl phosphonic acid (AEP), are tuned with the pH of the dispersion. The key to colloidal stability is electrostatic stabilization of the monolayer. This work demonstrates a means of mimicking the stabilizing power of a thiolate-bound ligand with a zwitterionic tail group, but without the thiolate binding group.
| Original language | English |
|---|---|
| Pages (from-to) | 14469-14474 |
| Number of pages | 6 |
| Journal | Chemistry - A European Journal |
| Volume | 25 |
| Issue number | 63 |
| DOIs | |
| Publication status | Published - Nov 13 2019 |
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Keywords
- catalysis
- ligand design
- nanotechnology
- quantum dots
- water chemistry
ASJC Scopus subject areas
- Catalysis
- Organic Chemistry
Cite this
Colloidally Stable CdS Quantum Dots in Water with Electrostatically Stabilized Weak-Binding, Sulfur-Free Ligands. / Arcudi, Francesca; Westmoreland, Dana Emily; Weiss, Emily Allyn.
In: Chemistry - A European Journal, Vol. 25, No. 63, 13.11.2019, p. 14469-14474.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Colloidally Stable CdS Quantum Dots in Water with Electrostatically Stabilized Weak-Binding, Sulfur-Free Ligands
AU - Arcudi, Francesca
AU - Westmoreland, Dana Emily
AU - Weiss, Emily Allyn
PY - 2019/11/13
Y1 - 2019/11/13
N2 - Colloidal quantum dot (QD) photocatalysts have the electrochemical and optical properties to be highly effective for a range of redox reactions. QDs are proven photo-redox catalysts for a variety of reactions in organic solvents but are less prominent for aqueous reactions. Aqueous QD photocatalysts require hydrophilic ligand shells that provide long-term colloidal stability but are not so tight-binding as to prevent catalytic substrates from accessing the QD surface. Common thiolate ligands, which also poison many co-catalysts and undergo photo-oxidative desorption, are therefore often not an option. This paper describes a framework for the design of water-solubilizing ligands that are in dynamic exchange on and off the QD surface, but still provide long-term colloidal stability to CdS QDs. The binding affinity and inter-ligand electrostatic interactions of a bifunctional ligand, aminoethyl phosphonic acid (AEP), are tuned with the pH of the dispersion. The key to colloidal stability is electrostatic stabilization of the monolayer. This work demonstrates a means of mimicking the stabilizing power of a thiolate-bound ligand with a zwitterionic tail group, but without the thiolate binding group.
AB - Colloidal quantum dot (QD) photocatalysts have the electrochemical and optical properties to be highly effective for a range of redox reactions. QDs are proven photo-redox catalysts for a variety of reactions in organic solvents but are less prominent for aqueous reactions. Aqueous QD photocatalysts require hydrophilic ligand shells that provide long-term colloidal stability but are not so tight-binding as to prevent catalytic substrates from accessing the QD surface. Common thiolate ligands, which also poison many co-catalysts and undergo photo-oxidative desorption, are therefore often not an option. This paper describes a framework for the design of water-solubilizing ligands that are in dynamic exchange on and off the QD surface, but still provide long-term colloidal stability to CdS QDs. The binding affinity and inter-ligand electrostatic interactions of a bifunctional ligand, aminoethyl phosphonic acid (AEP), are tuned with the pH of the dispersion. The key to colloidal stability is electrostatic stabilization of the monolayer. This work demonstrates a means of mimicking the stabilizing power of a thiolate-bound ligand with a zwitterionic tail group, but without the thiolate binding group.
KW - catalysis
KW - ligand design
KW - nanotechnology
KW - quantum dots
KW - water chemistry
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UR - http://www.scopus.com/inward/citedby.url?scp=85074100397&partnerID=8YFLogxK
U2 - 10.1002/chem.201903908
DO - 10.1002/chem.201903908
M3 - Article
C2 - 31486120
AN - SCOPUS:85074100397
VL - 25
SP - 14469
EP - 14474
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
SN - 0947-6539
IS - 63
ER -