jz0c02274_si_001.pdf (269.3 kB)
Electronic Tunability and Mobility Anisotropy of Quasi-2D Perovskite Single Crystals with Varied Spacer Cations
journal contribution
posted on 2020-08-28, 15:03 authored by Yu Zhang, Mingzi Sun, Ning Zhou, Bolong Huang, Huanping ZhouThe
organic–inorganic hybrid quasi-two-dimensional (quasi-2D)
perovskites have attracted increasing attention for solar cell applications
due to their improved moisture stability and excellent optoelectronic
properties. To achieve a profound understanding and delicate control
on the component of perovskite, it is indispensable to know how different
spacer cations affect their intrinsic properties. Here, we synthesized
a series of quasi-2D perovskite single crystals with different organic
spacer cations and conducted a systematic investigation to correlate
the optoelectronic behaviors to the spacer cations. We revealed the
coupling effect between the π-electron (PEA+) and
p orbital of I– from the inorganic framework, which
changed the electronic configuration of resultant crystals leading
to different band gap and carrier behavior. In particular, the anisotropic
carrier mobility was probed quantitatively by space-charge limited
current (SCLC) measurement, where PEA2MA2Pb3I10 exhibited the highest in-plane mobility due
to the reduced exciton binding energy and the lowest out-of-plane
mobility because of the widest organic barrier.