skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Solid state photon upconversion utilizing thermally activated delayed fluorescence molecules as triplet sensitizer

Journal Article · · Applied Physics Letters
DOI:https://doi.org/10.1063/1.4926914· OSTI ID:1196453

The ability to upconvert light is useful for a range of applications, from biological imaging to solar cells. But modern technologies have struggled to upconvert incoherent incident light at low intensities. In this work, we report solid state photon upconversion employing triplet-triplet exciton annihilation in an organic semiconductor, sensitized by a thermally activated-delayed fluorescence (TADF) dye. Compared to conventional phosphorescent sensitizers, the TADF dye maximizes the wavelength shift in upconversion due to its small singlet-triplet splitting. The efficiency of energy transfer from the TADF dye is 9.1%, and the conversion yield of sensitizer exciton pairs to singlet excitons in the annihilator is 1.1%. These conclusions demonstrate upconversion in solid state geometries and with non-heavy metal-based sensitizer materials.

Research Organization:
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
Grant/Contract Number:
FG02-07ER46474; DMR-1419807
OSTI ID:
1196453
Alternate ID(s):
OSTI ID: 1420550; OSTI ID: 1547023
Journal Information:
Applied Physics Letters, Journal Name: Applied Physics Letters Vol. 107 Journal Issue: 3; ISSN 0003-6951
Publisher:
American Institute of PhysicsCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 74 works
Citation information provided by
Web of Science

References (15)

Observation of two-photon emission from semiconductors journal March 2008
Detailed Balance Limit of Efficiency of p‐n Junction Solar Cells journal March 1961
Can up- and down-conversion and multi-exciton generation improve photovoltaics? journal December 2008
Effects of Magnetic Fields on the Mutual Annihilation of Triplet Excitons in Anthracene Crystals journal January 1970
A Theory of Sensitized Luminescence in Solids journal May 1953
Photon Upconversion by Triplet–Triplet Annihilation in Ru(bpy) 3 - and DPA-Functionalized Polymers journal November 2013
Light upconversion by triplet–triplet annihilation in diphenylanthracene-based copolymers journal January 2014
Highly efficient organic light-emitting diodes from delayed fluorescence journal December 2012
Characterization of triplet-triplet annihilation in organic light-emitting diodes based on anthracene derivatives journal December 2007
Triplet annihilation exceeding spin statistical limit in highly efficient fluorescent organic light-emitting diodes journal December 2009
Texaphyrin sensitized near-IR-to-visible photon upconversion journal January 2014
Dual enhancement of electroluminescence efficiency and operational stability by rapid upconversion of triplet excitons in OLEDs journal February 2015
Photon upconversion based on sensitized triplet–triplet annihilation journal November 2010
High efficiency non-dopant blue organic light-emitting diodes based on anthracene-based fluorophores with molecular design of charge transport and red-shifted emission proof journal January 2014
Exciton Quenching Behavior of Thermally Activated Delayed Fluorescence Molecules by Charge Carriers journal March 2015