skip to main content


Title: Supersonically Spray-Coated Colloidal Quantum Dot Ink Solar Cells

Controlling the thickness of quantum dot (QD) films is difficult using existing film formation techniques, which employ pre-ligand-exchanged PbS QD inks, because of several issues: 1) poor colloidal stability, 2) use of high-boiling-point solvents for QD dispersion, and 3) limitations associated with one-step deposition. Here in this paper, we suggest a new protocol for QD film deposition using electrical double-layered PbS QD inks, prepared by solution-phase ligand exchange using methyl ammonium lead iodide (MAPbI 3). The films are deposited by the supersonic spraying technique, which facilitates the rapid evaporation of the solvent and the subsequent deposition of the PbS QD ink without requiring a post-deposition annealing treatment for solvent removal. The film thickness could be readily controlled by varying the number of spraying sweeps made across the substrate. This spray deposition process yields high-quality n-type QD films quickly (within 1 min) while minimizing the amount of the PbS QD ink used to less than 5 mg for one device (300-nm-thick absorbing layer, 2.5 x 2.5 cm 2). Further, the formation of an additional p-layer by treatment with mercaptopropionic acid allows for facile hole extraction from the QD films, resulting in a power conversion efficiency of 3.7% under 1.5 AM illumination.
 [1] ;  [2] ;  [3] ;  [4] ;  [2] ; ORCiD logo [1]
  1. Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of). Nano-Mechanical Systems Research Division; Korea Univ. of Science and Technology (UST) Daejeon (Korea, Republic of)
  2. Korea Univ., Seoul (Korea, Republic of). School of Mechanical Engineering
  3. Korea Inst. of Machinery and Materials, Daejeon (Korea, Republic of)
  4. National Renewable Energy Lab. (NREL), Golden, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2045-2322
Grant/Contract Number:
AC36-08GO28308; NRF-2016R1A2B3014182
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Nature Publishing Group
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); Korea Institute for Advancement of Technology (KIAT)
Country of Publication:
United States
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; quantum dots; solar cells; deposition
OSTI Identifier: