Solution phase surface functionalization of PbS nanoparticles with organic ligands for single-step deposition of p-type layer of quantum dot solar cells

Beygi, H.; Sajjadi, Seyed Abdolkarim; Babakhani, Abolfazl; Young, Jeff F.; Veggel, Frank C. J. M. van

doi:10.1016/j.apsusc.2018.08.056

Cited by 19 publications

(10 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For I – /MPA-PbS QD films, it is well established that the thiol groups of MPA ligands bond to metal chalcogenide surfaces. ,,− Furthermore, the frequencies of the symmetric and antisymmetric C–O stretch modes of MPA ligands are similar to those found in the OA-PbS QD films for which the carboxylates are bonded to the nanocrystal surfaces. Prior work correlating infrared spectroscopy and X-ray crystallography of carboxylate groups in ionic solids demonstrates that such frequencies occur when the carboxylates are bonded to metal ions.…”

Section: Resultsmentioning

confidence: 67%

Influence of Ligand Structure on Excited State Surface Chemistry of Lead Sulfide Quantum Dots

et al. 2021

View full text Add to dashboard Cite

The ligand-nanocrystal boundaries of colloidal quantum dots (QDs) mediate the primary energy and electron transfer processes that underpin photochemical and photocatalytic transformations at their surfaces. We use mid-infrared transient absorption spectroscopy to reveal the influence that ligand structure and bonding to nanocrystal surfaces have on the changes of the excited state surface chemistry of this boundary in PbS QDs and the corresponding impact on charge transfer processes between nanocrystals. We demonstrate that oleate ligands undergo marked changes in their bonding to surfaces in the excitonic excited states of the nanocrystals, indicating that oleate passivated PbS surfaces undergo significant structural changes following photoexcitation. These changes can impact the surface mobility of the ligands and the ability of redox shuttles to approach the nanocrystal surfaces to undergo charge transfer in photocatalytic reactions. In contrast, markedly different transient vibrational features are observed in iodide/mercaptoproprionic acid passivated PbS QD films that result from charge transfer between neighboring nanocrystals and localization of holes at the nanocrystal surfaces near MPA ligands. This ability to distinguish the influence that excitonic excited states vs charge transfer processes have on the surface chemistry of the ligand-nanocrystal boundary lays the groundwork for exploration of how this boundary can be understood and controlled for the design of nanocrystalline materials tailored for specific applications in solar energy harvesting and photocatalytic reactions.

show abstract

Section: Resultsmentioning

confidence: 67%

Influence of Ligand Structure on Excited State Surface Chemistry of Lead Sulfide Quantum Dots

et al. 2021

View full text Add to dashboard Cite

show abstract

“…PbS CQDs are successfully employed in solar cells, light-emitting diodes, light-emitting transistors, , inverters, and photodetectors . For many years, one of the limiting steps in the fabrication of CQD devices has been the exchange of ligands in solid films which required layer-by-layer processing . In the last 12 years, the so-called phase-transfer ligand exchange (PTLE) has been adopted for small inorganic ligands, , namely chalcogenides and metal chalcogenide complexes, pseudohalides, halides, and halometallate complexes. − …”

Section: Introductionmentioning

confidence: 99%

“…7 For many years, one of the limiting steps in the fabrication of CQD devices has been the exchange of ligands in solid films which required layer-by-layer processing. 8 In the last 12 years, the so-called phase-transfer ligand exchange (PTLE) has been adopted for small inorganic ligands, 9,10 namely chalcogenides and metal chalcogenide complexes, pseudohalides, halides, and halometallate complexes. 11−17 PTLE results in a solution of ligand-exchanged CQDs (socalled inks), which can be used for the deposition of conductive CQD films by various deposition techniques, such as spin-coating, blade-coating, slot-die coating, dipcoating, and spray-coating.…”

Section: ■ Introductionmentioning

confidence: 99%

On the Colloidal Stability of PbS Quantum Dots Capped with Methylammonium Lead Iodide Ligands

Bederak

Sukharevska

Kahmann

et al. 2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Phase-transfer exchange of pristine organic ligands for inorganic ones is essential for the integration of colloidal quantum dots (CQDs) in optoelectronic devices. This method results in a colloidal dispersion (ink) which can be directly deposited by various solution-processable techniques to fabricate conductive films. For PbS CQDs capped with methylammonium lead iodide ligands (MAPbI 3 ), the most commonly employed solvent is butylamine, which enables only a short-term (hours) colloidal stability and thus brings concerns on the possibility of manufacturing CQD devices on a large scale in a reproducible manner. In this work, we studied the stability of alternative inks in two highly polar solvents which impart long-term colloidal stability of CQDs: propylene carbonate (PC) and 2,6-difluoropyridine (DFP). The aging and the loss of the ink’s stability were monitored with optical, structural, and transport measurements. With these solvents, PbS CQDs capped with MAPbI 3 ligands retain colloidal stability for more than 20 months, both in dilute and concentrated dispersions. After 17 months of ink storage, transistors with a maximum linear mobility for electrons of 8.5 × 10 –3 cm 2 /V s are fabricated; this value is 17% of the one obtained with fresh solutions. Our results show that both PC- and DFP-based PbS CQD inks offer the needed shelf life to allow for the development of a CQD device technology.

show abstract

“…Synthesis of PbS QDs and ligand exchange process with 3-MPA were done using previously reported methods. , A brief description of such processes can also be found in Supporting Information.…”

Section: Methodsmentioning

confidence: 99%

Halide-, Hybrid-, and Perovskite-Functionalized Light Absorbing Quantum Materials of p–i–n Heterojunction Solar Cells

Beygi

Sajjadi

Babakhani

et al. 2018

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

The p-i-n quantum dot (QD) solar cells were fabricated through the single-step deposition of both of its p-type and light absorbing quantum layers. The hole transport and light absorbing layers of these devices were made by the p- and n-type PbS QDs, which were functionalized with mercaptopropionic acid and different halide, hybrid, and perovskite ligands, respectively. Fabrication of such p-i-n devices by the single-step deposition of pre-exchanged colloidal QDs had not been fully investigated so far because of the low progression of ligand exchange processes, weak colloidal stability of pre-exchanged QDs in desired solvents, and remaining of the ligand exchange products along with particles. However, we showed that the type of ligand complexes, amino acid products of ligand exchange, and protic solvents are highly effective for increasing the ligand exchange progression and preparation of high colloidal stability QDs with superior photoluminescence properties. As well, the surface chemistry investigations by the means of Fourier transform infrared, nuclear magnetic resonance, X-ray photoelectron spectroscopy, X-ray diffraction, inductively coupled plasma optical emission spectrometry, carbon-hydrogen-nitrogen-sulfur elemental analysis, zeta potential, and high-resolution transmission electron microscopy were led to the presentation of new concepts about the theoretical and experimental ligand weight percentages, the mechanisms of solution-phase ligand exchange processes, and formation of ligands adlayer on the (111) facets of QDs. The pre-exchanged colloidal QDs showed very good desirability for the single-step deposition of dense, defects-free, and smooth QD layers. Regarding that, the p-i-n solar cells were successfully fabricated by the single-step deposition of both of the QD layers. Especially, the highest power conversion efficiency value of 6.40% was recorded for the devices in which the light absorbing layer was prepared by the composite-like QD-perovskite structures.

show abstract

Solution phase surface functionalization of PbS nanoparticles with organic ligands for single-step deposition of p-type layer of quantum dot solar cells

Cited by 19 publications

References 60 publications

Influence of Ligand Structure on Excited State Surface Chemistry of Lead Sulfide Quantum Dots

Influence of Ligand Structure on Excited State Surface Chemistry of Lead Sulfide Quantum Dots

On the Colloidal Stability of PbS Quantum Dots Capped with Methylammonium Lead Iodide Ligands

Halide-, Hybrid-, and Perovskite-Functionalized Light Absorbing Quantum Materials of p–i–n Heterojunction Solar Cells

Contact Info

Product

Resources

About