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09:57
Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Ultrafast intersystem-crossing in platinum containing π-conjugated polymers with tunable spin-orbit coupling.
C-X Sheng1, S Singh, A Gambetta
11] Department of Physics & Astronomy, University of Utah, Salt Lake City, Utah 84112, USA [2] School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, 210094, China [3].
Scientific Reports
|September 14, 2013
Summary
Researchers synthesized platinum-containing polymers for efficient organic electronics. These materials exhibit record-fast intersystem crossing (ISC) rates, enabling tunable light emission for applications like white organic light-emitting diodes (OLEDs).
Area of Science:
- Materials Science
- Organic Electronics
- Photophysics
Background:
- Efficient organic light-emitting diodes (OLEDs) and organic photovoltaic cells depend on controlling spin dynamics.
- Heavy metal atom incorporation in conjugated polymers enhances spin-orbit coupling (SOC), promoting intersystem crossing (ISC).
Purpose of the Study:
- To investigate the energies, emission bands, and ultrafast dynamics of spin photoexcitations in novel platinum-containing π-conjugated polymers.
- To establish a link between controllable SOC and ISC rates for tailored optoelectronic properties.
Main Methods:
- Synthesis of two new π-conjugated polymers with intrachain platinum (Pt) atoms (Pt-1 and Pt-3).
- Nonlinear optical spectroscopies: two-photon absorption and electroabsorption.
- Electronic structure calculations.
Main Results:
- Record intersystem crossing (ISC) times achieved: <~1 ps for Pt-1 and ~6 ps for Pt-3.
- Demonstrated tunable ISC rates by varying the number of organic spacer units between Pt atoms.
- Observed modulation of phosphorescence and fluorescence intensity ratios.
Conclusions:
- Controllable SOC in Pt-containing polymers enables ultrafast ISC.
- The tunable ISC rates offer potential for developing advanced white OLEDs.
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