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Title: SELF-HEALING NANOMATERIALS: MULTIMILLION-ATOM REACTIVE MOLECULAR DYNAMICS SIMULATIONS

Organometal halide perovskites are attracting great attention as promising material for solar cells because of their high power conversion efficiency. The high performance has been attributed to the existence of free charge carriers and their large diffusion lengths, but the nature of carrier transport at the atomistic level remains elusive. Here, nonadiabatic quantum molecular dynamics simulations elucidate the mechanisms underlying the excellent free-carrier transport in CH3NH3PbI3. Pb and I sublattices act as disjunct pathways for rapid and balanced transport of photoexcited electrons and holes, respectively, while minimizing efficiency-degrading charge recombination. On the other hand, CH3NH3 sublattice quickly screens out electrostatic electron-hole attraction to generate free carriers within 1 ps. Together this nano-architecture lets photoexcited electrons and holes dissociate instantaneously and travel far away to be harvested before dissipated as heat. As a result, this work provides much needed structure-property relationships and time-resolved information that potentially lead to rational design of efficient solar cells.
Authors:
 [1] ;  [2] ;  [1] ;  [3] ;  [3] ;  [3]
  1. Kumamoto Univ., Kumamoto (Japan)
  2. Kumamoto Univ., Kumamoto (Japan); Univ. of Southern California, Los Angeles, CA (United States); Kobe Univ., Kobe (Japan)
  3. Univ. of Southern California, Los Angeles, CA (United States)
Publication Date:
OSTI Identifier:
1238777
Report Number(s):
DOE-UCLA-46130
srep19599
DOE Contract Number:
FG02-04ER46130
Resource Type:
Technical Report
Research Org:
Univ. of California, Los Angeles, CA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
atomistic models; electronic structure