Lead-FreeCs4CuSb2Cl12 Layered Double PerovskiteNanocrystals
2020
Concerns
about the toxicity of lead-based perovskites have aroused
great interest for the development of alternative lead-free perovskite-type
materials. Recently, theoretical calculations predict that Pb2+ cations can be substituted by a combination of Cu2+ and Sb3+ cations to form a vacancy-ordered layered double
perovskite structure with superior optoelectronic properties. However,
accessibilities to this class of perovskite-type materials remain
inadequate, hindering their practical implementations in various applications.
Here, we report the first colloidal synthesis of Cs4CuSb2Cl12 perovskite-type nanocrystals (NCs). The resulting
NCs exhibit a layered double perovskite structure with ordered vacancies
and a direct band gap of 1.79 eV. A composition–structure–property
relationship has been established by investigating a series of Cs4CuxAg2–2xSb2Cl12 perovskite-type NCs (0 ≤ x ≤ 1). The composition induced crystal structure
transformation, and thus, the electronic band gap evolution has been
explored by experimental observations and further confirmed by theoretical
calculations. Taking advantage of both the unique electronic structure
and solution processability, we demonstrate that the Cs4CuSb2Cl12 NCs can be solution-processed as
high-speed photodetectors with ultrafast photoresponse and narrow
bandwidth. We anticipate that our study will prompt future research
to design and fabricate novel and high-performance lead-free perovskite-type
NCs for a range of applications.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
0
Citations
NaN
KQI