Two‐Phase Approach to High‐Quality, Oil‐Soluble, Near‐Infrared‐Emitting PbS Quantum Dots by Using Various Water‐Soluble Anion Precursors

Abstract

Colloidal PbS quantum dots (QDs) with tunable photoemission throughout the near-infrared (NIR) region (ca. 750-1000 nm) were synthesized by a two-phase approach. Here, oil-soluble lead oleate formed by a reaction of lead acetate and oleic acid (OA, the capping agent) in n-decane at 130°C was used as lead precursor, and water-soluble Na 2 S, thioacetamide (TAA), and thiourea, each having a different reactivity, were used as sulfur sources. When an n-decane solution of lead precursor and an aqueous solution of sulfur pre-

Synthesis of Various Sized CuInS2 Quantum Dots and Their Photovoltaic Properties as Sensitizers for TiO2 Photoanodes

“…Semiconductor quantum‐dot (QD)‐sensitized solar cells have been proposed as the next generation of photovoltaic devices due to their narrow band gaps, large absorption edges, special photoelectric properties, and quantum size effect, which clearly may improve the photovoltaic conversion efficiency. CdTe,2 CdS,3,4 CdSe,5–7 and PbS8 are currently used as sensitizers for this purpose, however, they have a number of drawbacks, such as their band gap ( E g ), easy photodegradation in the visible‐light region, toxicity, and environmental pollution, which limits their widespread application in solar cells.…”

In vivo NIR imaging with PbS quantum dots entrapped in biodegradable micelles

“…PbS QDs were synthesized according to our previous approach. 42 The reactor setup is depicted in Figure 1(A). Here, we used oleic acid as the capping agent and aqueous Na 2 S as the sulfur source.…”

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