Surface Chemistry and Quantum Dot Luminescence: Shell Growth, Atomistic Modification, and Beyond

Abstract

Quantum dots are used in the research laboratory and in commercial applications for their bright, size-tunable luminescence. While empirical synthesis and processing optimization have led to many quantum dot systems with photoluminescence quantum yields at or approaching 100%, our understanding of the chemical principles that underlie this performance and our ability to access such materials on demand have lagged. In this Perspective, we present the status of our understanding of the connections between surface chemistry and quantum dot luminescence. We follow the historical arc that began with shell growth, which then led to an atomistic description of surface-derived charge trapping, and finally has brought us to a more nuanced picture of the role of surface chemistry in luminescence properties, including emerging concepts like surface dipoles and vibronic coupling.

Synergistic Effect of Halogen Ions and Shelling Temperature on Anion Exchange Induced Interfacial Restructuring for Highly Efficient Blue Emissive InP/ZnS Quantum Dots

“…Indium phosphide (InP) QDs with wide emission range and no toxicity are promising alternative emitting material, rapidly acquiring extensive research, but it is still a great challenge to obtain high‐quality InP QDs. [ 15–18 ]…”

“…Indium phosphide (InP) QDs with wide emission range and no toxicity are promising alternative emitting material, rapidly acquiring extensive research, but it is still a great challenge to obtain highquality InP QDs. [15][16][17][18] To date, considerable research has focused on growth kinetics and synthetic strategies of InP QDs. [19][20][21][22][23][24][25] Apart from the common method where indium acetate and tris(trimethylsilyl)phosphine ((TMS) 3 P) are utilized, indium halide is widely employed in the preparation of InP/ ZnS QDs combining with zinc halide and amino phosphine recently owing to its low cost and safety.…”

Luminescence Enhancement, Encapsulation, and Patterning of Quantum Dots Toward Display Applications

“…In this section, we will focus on the external encapsulation of enveloping the entire QDs (including the core, shell, and ligand), and will only provide a brief introduction to the surface engineering because there are already many review reports in the literature. [81][82][83][84] The main methods are illustrated in Figure 6 and summarized in Table 2.…”

Precursor chemistry of metal nitride nanocrystals

“…and also their surface chemistry is increasingly better understood. [10][11][12][13][14][15][16] The crystallization mechanism (i.e., nucleation and growth) causes more discussion in the literature. 17,18 Approaches based on classical nucleation theory are at odds with the Finke-Watzky based mechanisms.…”

“…Using the same strategy as mentioned before, In is removed by an nitric acid treatment and the InN NCs are stabilized by functionalization with OLAm. 176 Intrigued by the high dissociation energy of C-N bonds (330 kJ mol −1 ), Beaulac et al investigated the mechanism of this reaction by analyzing the by-products via 1 H NMR, 13 C NMR, 2D COSY NMR, and mass spectrometry. 177 The authors propose that oleylamide is oxidized to oleylimine, thereby reducing In(III) to In(0), see Fig.…”