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Title: p-Type molecular doping by charge transfer in halide perovskite
Electronic technologies critically rely on the ability to broadly dope the active semiconductor; yet the promising class of halide perovskite semiconductors so far does not allow for significant control over carrier type (p- or n-) and density. The molecular doping approach offers important opportunities for generating free carriers through charge transfer. In this work, we demonstrate effective p-doping of MAPb 0.5 Sn 0.5 I 3 films using the molecular dopant F4TCNQ as a grain boundary coating, offering a conductivity and hole density tuning range of up to five orders of magnitude, associated with a 190 meV Fermi level down-shift. While charge transfer between MAPb 0.5 Sn 0.5 I 3 and F4TCNQ appears efficient, dopant ionization decreases with increasing Pb content, highlighting the need for appropriate energy offset between host and dopant molecule. Finally, we show that electrical p-doping impacts the perovskite optoelectronic properties, with a hole recombination lifetime increase of over one order of magnitude, suggesting passivation of deep traps.  more » « less
Award ID(s):
1807797 2004869
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Materials Advances
Medium: X
Sponsoring Org:
National Science Foundation
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