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Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites.

ABSTRACT: A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An unusual large blue shift of the time-integrated photoluminescence with increasing excitation power (150?meV at 24?K and 75?meV at 293?K) is displayed. On the basis of the analysis of energy-resolved and time-resolved photoluminescence, we posit that these phenomena are associated with slow hot carrier relaxation and state-filling of band edge states. These observations are both important for our understanding of lead-free hybrid perovskites and for an eventual future development of efficient lead-free perovskite photovoltaics.

SUBMITTER: Fang HH

PROVIDER: S-EPMC5770436 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites.

Fang Hong-Hua HH Adjokatse Sampson S Shao Shuyan S Even Jacky J Loi Maria Antonietta MA

Nature communications 20180116 1

A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An unusual large blue shift of the time-integrated photoluminescence with increasing excitation power (150 meV at 24 K and 75 meV at 293 K) is displayed. On the basis of the analysis of energy-resolved and t ...[more]

PMID: 29339814

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