Imperial College London
Portrait Picture

Dr Jarvist Moore Frost

Faculty of Natural Sciences, Department of Chemistry

Royal Society URF (Lecturer)
 
 
 
//

Contact

 

jarvist.frost Website

 
 
//

Location

 

601FMolecular Sciences Research HubWhite City Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Frost:2017:10.1021/acsenergylett.7b00862,
author = {Frost, JM and Whalley, LD and Walsh, A},
doi = {10.1021/acsenergylett.7b00862},
journal = {ACS Energy Letters},
pages = {2647--2652},
title = {Slow cooling of hot polarons in halide perovskite solar cells},
url = {http://dx.doi.org/10.1021/acsenergylett.7b00862},
volume = {2},
year = {2017}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Halide perovskites show unusual thermalisation kinetics for above bandgapphoto-excitation. We explain this as a consequence of excess energy beingdeposited into discrete large polaron states. The cross-over betweenlow-fluence and high-fluence `phonon bottleneck' cooling is due to a Motttransition where the polarons overlap ($n \ge 10^{18}/\mathrm{cm}^3$) and thephonon sub-populations are shared. We calculate the initial rate of cooling(thermalisation) from the scattering time in the Fr\"ohlich polaron model to be78 meVps$^{-1}$ for $\mathrm{CH}_3\mathrm{NH}_3\mathrm{PbI}_3$. This rapidinitial thermalisation involves heat transfer into optical phonon modes coupledby a polar dielectric interaction. Further cooling to equilibrium over hundredsof picoseconds is limited by the ultra-low thermal conductivity of theperovskite lattice.
AU  - Frost,JM
AU  - Whalley,LD
AU  - Walsh,A
DO  - 10.1021/acsenergylett.7b00862
EP  - 2652
PY  - 2017///
SN  - 2380-8195
SP  - 2647
TI  - Slow cooling of hot polarons in halide perovskite solar cells
T2  - ACS Energy Letters
UR  - http://dx.doi.org/10.1021/acsenergylett.7b00862
VL  - 2
ER  -
Download