1120-46-3Relevant articles and documents
Control of PbSe nanorod aspect ratio by limiting phosphine hydrolysis
Boercker, Janice E.,Foos, Edward E.,Placencia, Diogenes,Tischler, Joseph G.
, p. 15071 - 15076 (2013)
The aspect ratio and yield of PbSe nanorods synthesized by the reaction of Pb-oleate with tris(diethylamino)phosphine selenide are highly sensitive to the presence of water, making it critical to control the amount of water present in the reaction. By car
Colloidal Nanocrystals as a Platform for Rapid Screening of Charge Trap Passivating Molecules for Metal Halide Perovskite Thin Films
Alpert, Matthew R.,Niezgoda, J. Scott,Chen, Alexander Z.,Foley, Benjamin J.,Cuthriell, Shelby,Yoon, Lucy U.,Choi, Joshua J.
, p. 4515 - 4526 (2018)
Charge recombination at surface trap sites is a significant impediment to metal halide perovskite (MHP) thin film-based optoelectronic devices. To passivate the surface charge traps, chemical treatments with molecules that bind to the MHP thin film surfaces can be employed. However, the current approaches to test the trap passivation efficacy of molecules on thin film surface suffer from limited through-put and low statistical significance. Here, we demonstrate the use of colloidal MHP nanocrystals (NCs) as an experimental platform for high-throughput screening of charge trap passivating molecules for MHP thin films. Using CsPbX3 (X = Br, I) NCs, over 20 molecules were rapidly screened for their surface trap passivation efficacy. Our approach identified trin-butylphosphine (TBPh) as a superb charge trap passivating molecule on MHP surfaces. TBPh treatment brings the photoluminescence quantum yield of CsPbBr3 NCs to near unity and also results in superior surface trap passivation of MHP thin films, even when compared to a previously reported treatment with pyridine. Our work highlights the benefits of utilizing the high surface area-to-volume ratio of NCs for the accelerated study of surface trap passivation using molecular treatment and then translating the findings to bulk semiconductors. This approach is broadly applicable to a wide range of semiconductors as long as they can be synthesized into NCs.
Steric-hindrance-driven shape transition in PbS quantum dots: Understanding size-dependent stability
Choi, Hyekyoung,Ko, Jae-Hyeon,Kim, Yong-Hyun,Jeong, Sohee
, p. 5278 - 5281 (2013)
Ambient stability of colloidal nanocrystal quantum dots (QDs) is imperative for low-cost, high-efficiency QD photovoltaics. We synthesized air-stable, ultrasmall PbS QDs with diameter (D) down to 1.5 nm, and found an abrupt transition at D ≈ 4 nm in the a
Quantum confinement-tunable ultrafast charge transfer at the PbS quantum dot and phenyl-C61-butyric acid methyl ester interface
El-Ballouli, Alaa O.,Alarousu, Erkki,Bernardi, Marco,Aly, Shawkat M.,Lagrow, Alec P.,Bakr, Osman M.,Mohammed, Omar F.
, p. 6952 - 6959 (2014)
Quantum dot (QD) solar cells have emerged as promising low-cost alternatives to existing photovoltaic technologies. Here, we investigate charge transfer and separation at PbS QDs and phenyl-C61-butyric acid methyl ester (PCBM) interfaces using a combination of femtosecond broadband transient absorption (TA) spectroscopy and steady-state photoluminescence quenching measurements. We analyzed ultrafast electron injection and charge separation at PbS QD/PCBM interfaces for four different QD sizes and as a function of PCBM concentration. The results reveal that the energy band alignment, tuned by the quantum size effect, is the key element for efficient electron injection and charge separation processes. More specifically, the steady-state and time-resolved data demonstrate that only small-sized PbS QDs with a bandgap larger than 1 eV can transfer electrons to PCBM upon light absorption. We show that these trends result from the formation of a type-II interface band alignment, as a consequence of the size distribution of the QDs. Transient absorption data indicate that electron injection from photoexcited PbS QDs to PCBM occurs within our temporal resolution of 120 fs for QDs with bandgaps that achieve type-II alignment, while virtually all signals observed in smaller bandgap QD samples result from large bandgap outliers in the size distribution. Taken together, our results clearly demonstrate that charge transfer rates at QD interfaces can be tuned by several orders of magnitude by engineering the QD size distribution. The work presented here will advance both the design and the understanding of QD interfaces for solar energy conversion.
Spontaneous multielectron transfer from the surfaces of PbS quantum dots to tetracyanoquinodimethane
Knowles, Kathryn E.,Malicki, Michal,Parameswaran, Radha,Cass, Laura C.,Weiss, Emily A.
, p. 7264 - 7271 (2013)
This paper describes an investigation of the interfacial chemistry that enables formation of a multielectron ground-state charge-transfer (CT) complex of oleate-coated PbS quantum dots (QDs) and tetracyanoquinodimethane (TCNQ) in CHCl3 dispersions. Thermodynamically spontaneous electron transfer occurs from sulfur ions on the surfaces of the QDs (radius = 1.6 nm) to adsorbed TCNQ molecules and creates indefinitely stable ion pairs that are characterized by steady-state visible and mid-infrared absorption spectroscopy of reduced TCNQ and by NMR spectroscopy of the protons of oleate ligands that coat the QDs. The combination of these techniques shows that (i) each QD reduces an average of 4.5 TCNQ molecules, (ii) every electron transfer event between the QD and TCNQ occurs at the QD surface, (iii) sulfur ions on the surfaces of the QDs (and not delocalized states within the QDs) are the electron donors, and (iv) some TCNQ molecules adsorb directly to the surface of the QDs while others adsorb upon displacement of oleate ligands.
Use of sulfur and selenium compounds as precursors to nanostructured materials
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Page/Page column 23, (2019/04/26)
The presently disclosed subject matter provides processes for preparing nanocrystals, including processes for preparing core-shell nanocrystals. The presently disclosed subject matter also provides sulfur and selenium compounds as precursors to nanostructured materials. The presently disclosed subject matter also provides nanocrystals having a particular particle size distribution.
METHODS OF PRODUCING METAL SUFLIDES, METAL SELENIDES, AND METAL SULFIDES/SELENIDES HAVING CONTROLLED ARCHITECTURES USING KINETIC CONTROL
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Paragraph 0222, (2017/05/28)
The present invention is directed to methods of preparing metal sulfide, metal selenide, or metal sulfide/selenide nanoparticles and the products derived therefrom. In various embodiments, the nanoparticles are derived from the reaction between precursor metal salts and certain sulfur- and/or selenium-containing precursors each independently having a structure of Formula (I), (II), or (III), or an isomer, salt, or tautomer thereof, where Q1,Q2,Q3,R1,R2,R3,R5, and X are defined within the specification.
