title: Thickness-Controlled Quasi-Two-Dimensional Colloidal PbSe Nanoplatelets.
abstract: We demonstrate controlled synthesis of discrete two-dimensional (2D) PbSe nanoplatelets (NPLs), with measurable photoluminescence, via oriented attachment directed by quantum dot (QD) surface chemistry. Halide passivation is critical to the growth of these (100) face-dominated NPLs, as corroborated by density functional theory studies. PbCl2moieties attached to the (111) and (110) of small nanocrystals form interparticle bridges, aligning the QDs and leading to attachment. We find that a 2D bridging network is energetically favored over a 3D network, driving the formation of NPLs. Although PbI2does not support bridging, its presence destabilizes the large (100) faces of NPLs, providing means for tuning NPL thickness. Spectroscopic analysis confirms the predicted role of thickness-dependent quantum confinement on the NPL band gap.
authors.affiliation: Center for Advanced Solar Photophysics, C-PCS, Chemistry Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States.
authors.forename: Weon-Kyu
authors.initials: WK
authors.lastname: Koh
authors.affiliation: Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States.
authors.forename: Naveen K
authors.initials: NK
authors.lastname: Dandu
authors.affiliation: Center for Advanced Solar Photophysics, C-PCS, Chemistry Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Fidler
authors.affiliation: Center for Advanced Solar Photophysics, C-PCS, Chemistry Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States.
authors.forename: Victor I
authors.identifier: 0000-0003-1158-3179
authors.initials: VI
authors.lastname: Klimov
authors.affiliation: Center for Advanced Solar Photophysics, C-PCS, Chemistry Division, Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States.
authors.forename: Jeffrey M
authors.identifier: 0000-0001-5360-4228
authors.initials: JM
authors.lastname: Pietryga
authors.affiliation: Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108, United States.
authors.forename: Svetlana V
authors.identifier: 0000-0003-1350-2790
authors.initials: SV
authors.lastname: Kilina