Emergent Electronic and Dielectric Properties of Interacting Nanoparticles at Finite Temperature

Journal Article · Mon Dec 11 00:00:00 EST 2017 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.7b04047· OSTI ID:1421969

Greenwood, Arin R. ^[1]; Voros, Marton ^[2]; Giberti, Federico ^[1]; Galli, Giulia ^[3]

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1. The Univ. of Chicago, Chicago, IL (United States)
2. Argonne National Lab. (ANL), Argonne, IL (United States)
3. The Univ. of Chicago, Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)

Lead chalcogenide nanoparticle solids have been successfully integrated into certified solar cells and represent promising platforms for the design of novel photoabsorbers for photoelectrochemical cells. While much attention has been drawn to improving efficiency and device performance through altering the character of the individual nanoparticles, the role of interactions between nanoparticles is not yet well-understood. Using first-principles molecular dynamics and electronic structure calculations, we investigated the combined effect of temperature and interaction on functionalized lead chalcogenide nanoparticles (NPs). Here, we show that at finite temperature, interacting NPs are dynamical dipolar systems, with the average values of dipole moments and polarizabilities substantially increased with respect to those of the isolated building blocks. In addition, we show that the interacting NPs exhibit slightly smaller fundamental gaps that decrease as a function of temperature and that the radiative lifetimes of both the isolated NPs and the solids are greatly reduced at finite temperature compared to T = 0. Lastly, we present a critical discussion of various results reported in the literature for the values of dipole moments of nanoparticles.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: Argonne National Laboratory; Centers for Chemical Innovation (CCI); Laboratory Directed Research and Development (LDRD); Midwest Integrated Center for Computational Materials (MICCoM); National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1421969
• Journal Information: Nano Letters, Journal Name: Nano Letters Journal Issue: 1 Vol. 18; ISSN 1530-6984
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
chalcogenide quantum dots
density functional theory
molecular dynamics
photovoltaic devices