Journal
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
Volume 9, Issue 16, Pages 4502-4511Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jpclett.8b01628
Keywords
-
Categories
Funding
- Enginneering and Physical Sciences Research Council (EPSRC) [EP/P033229/1, EP/P006329/1, EP/L024667/1]
- EPSRC Centre for Doctoral Training in New and Sustainable Photovoltaics [EP/L01551X/1]
- EPSRC [EP/L024667/1, EP/P033229/1, EP/P006329/1] Funding Source: UKRI
Ask authors/readers for more resources
Metal halide perovskites have proven to be excellent light-harvesting materials in photovoltaic devices whose efficiencies are rapidly improving. Here, we examine the temperature-dependent photon absorption, exciton binding energy, and band gap of FAPbI(3) (thin film) and find remarkably different behavior across the beta-gamma phase transition compared with MAPbI(3). While MAPbI(3) has shown abrupt changes in the band gap and exciton binding energy, values for FAPbI(3) vary smoothly over a range of 100-160 K in accordance with a more gradual transition. In addition, we find that the charge-carrier mobility in FAPbI(3) exhibits a clear T-0.5 trend with temperature, in excellent agreement with theoretical predictions that assume electron-phonon interactions to be governed by the Frohlich mechanism but in contrast to the T-0.5 dependence previously observed for MAPbI(3). Finally, we directly observe intraexcitonic transitions in FAPbI(3) at low temperature, from which we determine a low exciton binding energy of only 5.3 meV at 10 K.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available