Micron Thick Colloidal Quantum Dot Solids

Fan JZ, Vafaie M, Bertens K, Sytnyk M, Pina JM, Sagar LK, Ouellette O, Proppe AH, Rasouli AS, Gao Y, Baek SW, Chen B, Laquai F, Hoogland S, De Arquer FPG, Heiß W, Sargent EH (2020)

Publication Type: Journal article

Publication year: 2020

Journal

Nano Letters American Chemical Society

Book Volume: 20

Pages Range: 5284-5291

Journal Issue: 7

DOI: 10.1021/acs.nanolett.0c01614

Abstract

Shortwave infrared colloidal quantum dots (SWIR-CQDs) are semiconductors capable of harvesting across the AM1.5G solar spectrum. Today's SWIR-CQD solar cells rely on spin-coating; however, these films exhibit cracking once thickness exceeds ∼500 nm. We posited that a blade-coating strategy could enable thick QD films. We developed a ligand exchange with an additional resolvation step that enabled the dispersion of SWIR-CQDs. We then engineered a quaternary ink that combined high-viscosity solvents with short QD stabilizing ligands. This ink, blade-coated over a mild heating bed, formed micron-thick SWIR-CQD films. These SWIR-CQD solar cells achieved short-circuit current densities (Jsc) that reach 39 mA cm-2, corresponding to the harvest of 60% of total photons incident under AM1.5G illumination. External quantum efficiency measurements reveal both the first exciton peak and the closest Fabry-Perot resonance peak reaching approximately 80%-this is the highest unbiased EQE reported beyond 1400 nm in a solution-processed semiconductor.

Authors with CRIS profile

Mykhailo Sytnyk Institute Materials for Electronics and Energy Technology (i-MEET) Wolfgang Heiß Professur für Werkstoffwissenschaften (lösungsprozessierte Halbleitermaterialien)

Involved external institutions

University of Toronto CA Canada (CA) King Abdullah University of Science and Technology (KAUST) / جامعة الملك عبد الله للعلوم و التقنية SA Saudi Arabia (SA)

How to cite

APA:

Fan, J.Z., Vafaie, M., Bertens, K., Sytnyk, M., Pina, J.M., Sagar, L.K.,... Sargent, E.H. (2020). Micron Thick Colloidal Quantum Dot Solids. Nano Letters, 20(7), 5284-5291. https://dx.doi.org/10.1021/acs.nanolett.0c01614

MLA:

Fan, James Z., et al. "Micron Thick Colloidal Quantum Dot Solids." Nano Letters 20.7 (2020): 5284-5291.

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