TY - JOUR
T1 - Understanding Dark Current-Voltage Characteristics in Metal-Halide Perovskite Single Crystals
AU - Duijnstee, Elisabeth A.
AU - Le Corre, Vincent M.
AU - Johnston, Michael B.
AU - Koster, L. Jan Anton
AU - Lim, Jongchul
AU - Snaith, Henry J.
N1 - Funding Information:
This project is funded by the Engineering and Physical Sciences Research Council (EPSRC), Grants No. EP/M005143/1 and No. EP/S004947/1. E.A.D. thanks the EPSRC for funding via the Centre for Doctoral Training in New and Sustainable Photovoltaics. The work by V.M.L.C. is supported by a grant from STW/NWO (VIDI 13476).
Publisher Copyright:
© 2021 American Physical Society.
PY - 2021/1/6
Y1 - 2021/1/6
N2 - Hybrid halide perovskites have great potential for application in optoelectronic devices. However, an understanding of some basic properties, such as charge-carrier transport, remains inconclusive, mainly due to the mixed ionic and electronic nature of these materials. Here, we perform temperature-dependent pulsed-voltage space-charge-limited current measurements to provide a detailed look into the electronic properties of methylammonium lead tribromide (MAPbBr(3)) and methylammonium lead triiodide (MAPbI(3)) single crystals. We show that the background carrier density in these crystals is orders of magnitude higher than that expected from thermally excited carriers from the valence band. We highlight the complexity of the system via a combination of experiments and drift-diffusion simulations and show that different factors, such as thermal injection from the electrodes, temperature-dependent mobility, and trap and ion density, influence the free-carrier concentration. We experimentally determine effective activation energies for conductivity of (349 +/- 10) meV for MAPbBr3 and (193 +/- 12) meV for MAPbI(3), which includes the sum of all of these factors. We point out that fitting the dark current density-voltage curve with a drift-diffusion model allows for the extraction of intrinsic parameters, such as mobility and trap and ion density. From simulations, we determine a charge-carrier mobility of 12.9 cm(2)/Vs, a trap density of 1.52 x 10(13) cm(-3), and an ion density of 3.19 x 10(12) cm(-3) for MAPbBr(3) single crystals. Insights into charge-carrier transport in metal-halide perovskite single crystals will be beneficial for device optimization in various optoelectronic applications.
AB - Hybrid halide perovskites have great potential for application in optoelectronic devices. However, an understanding of some basic properties, such as charge-carrier transport, remains inconclusive, mainly due to the mixed ionic and electronic nature of these materials. Here, we perform temperature-dependent pulsed-voltage space-charge-limited current measurements to provide a detailed look into the electronic properties of methylammonium lead tribromide (MAPbBr(3)) and methylammonium lead triiodide (MAPbI(3)) single crystals. We show that the background carrier density in these crystals is orders of magnitude higher than that expected from thermally excited carriers from the valence band. We highlight the complexity of the system via a combination of experiments and drift-diffusion simulations and show that different factors, such as thermal injection from the electrodes, temperature-dependent mobility, and trap and ion density, influence the free-carrier concentration. We experimentally determine effective activation energies for conductivity of (349 +/- 10) meV for MAPbBr3 and (193 +/- 12) meV for MAPbI(3), which includes the sum of all of these factors. We point out that fitting the dark current density-voltage curve with a drift-diffusion model allows for the extraction of intrinsic parameters, such as mobility and trap and ion density. From simulations, we determine a charge-carrier mobility of 12.9 cm(2)/Vs, a trap density of 1.52 x 10(13) cm(-3), and an ion density of 3.19 x 10(12) cm(-3) for MAPbBr(3) single crystals. Insights into charge-carrier transport in metal-halide perovskite single crystals will be beneficial for device optimization in various optoelectronic applications.
KW - CHARGE-LIMITED CURRENTS
KW - SOLAR-CELLS
KW - TRANSPORT
KW - RECOMBINATION
KW - HYSTERESIS
U2 - 10.1103/PhysRevApplied.15.014006
DO - 10.1103/PhysRevApplied.15.014006
M3 - Article
SN - 2331-7019
VL - 15
JO - Physical Review Applied
JF - Physical Review Applied
IS - 1
M1 - 014006
ER -