SUPPORTING INFORMATION
Tunable Percolation in Semiconducting Binary Polymer Nanoparticle Glasses Lawrence A. Renna,† Monojit Bag,†,§ Timothy S. Gehan,† Xu Han,‡ Paul M. Lahti,† Dimitrios Maroudas,‡ D. Venkataraman*,† †
Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, U.S.A.
‡
Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003-9303, U.S.A. §
Present Address: Department of Physics, Indian Institute of Technology Roorkee, Rookee 247667, Uttarakhand, India *(DV) E-mail
[email protected] ph. (413) 545-2028
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Figure S1. (a) NTA results showing the concentration (# nanoparticles /mL) vs. diameter (nm) of separate dispersions of post-polymerization miniemulsion prepared P3HT and PS nanoparticles. (b) Tapping mode AFM of P3HT and PS nanoparticles. (c) Average SAXS profile of drop-cast binary P3HT/PS polymer nanoparticle glass (η ~ 60%). The SAXS intensity pattern is shown in the inset.
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Figure S2. Height and current maps respectively for (a),(b), η = 20% (c),(d), η = 40% (e),(f), η = 60% (g),(h), η = 70% (i),(j), and η = 80%. S3
Figure S4. (a) Pair correlation function for simulated disordered nanoparticle network assemblies. The green dashed line marks d + δ. (b) fraction of particles on the surface of a simulated assembly that have at least one percolation pathway to the planar electrode for h = 2.5, 3.0 and 6.0 with respect to η (c), common distribution for coordination angle S4
between any three connected particles in a simulated nanoparticle network, the most common coordination angle is 60°, result is reproduced for all h and η. Distributions for number of contacts for (d) h = 2.5 , (e) h = 3.0, (f) h = 6.0 for η = 10% - 90%. Simulated average effective surface current distributions for (g) h = 6.0, (h) h = 2.5, (i) h = 3.0 for η = 10% - 90%.
Table S1. Fraction of Particles on the Surface of Simulated Assembly That Have at Least One Percolation Pathway to the Bottom Planar Electrode for h = 2.5, 3.0 and 6.0 with respect to η
η 10% 20% 30% 40% 50% 60% 70% 80% 90%
h = 2.5 0.027 ± 0.053 0.206 ± 0.046 0.402 ± 0.051 0.666 ± 0.048 0.846 ± 0.013 0.941 ± 0.003 0.982 ± 0.003 0.995 ± 0.0 0.999 ± 0.0
h = 3.0 0.004 ± 0.050 0.121 ± 0.062 0.281 ± 0.035 0.607 ± 0.042 0.822 ± 0.011 0.980 ± 0.005 0.980 ± 0.005 0.993 ± 0.002 0.998 ± 0.001
h = 6.0 0.0 ± 0.048 0.0 ±0.026 0.037 ± 0.041 0.380 ± 0.018 0.738 ± 0.029 0.971 ± 0.019 0.972 ± 0.001 0.989 ± 0.003 0.999 ± 0.0
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Table S2. Mode Number of Connections of Simulated Disordered Nanoparticle Networks for Nanoparticles for h = 2.5, 3.0 and 6.0 for η from 10% to 90%.
η 10% 20% 30% 40% 50% 60% 70% 80% 90%
h = 2.5 0.0 0.909 ± 0.07 1.606 ± 0.10 2.256 ± 0.08 2.921 ± 0.01 3.513 ± 0.14 3.974 ± 0.05 4.510 ± 0.14 5.102 ± 0.04
h = 3.0 0.0 0.984 ± 0.16 1.833 ± 0.04 2.489 ± 0.04 3.293 ± 0.01 3.846 ± 0.09 4.333 ± 0.08 4.727 ± 0.05 5.170 ± 0.01
h = 6.0 0.0 1.073 ± 0.11 1.910 ± 0341 2.651 ± 0.04 3.411 ± 0.03 4.168 ± 0.05 4.891 ± 0.06 5.615 ± 0.07 6.426 ± 0.06
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Figure S5. TOF transients and results from numerical simulations of TOF data. TOF transients measured at 2V, 3V, 5V, 7V, and 10V for nanoparticle films with (a) η = 40%, (b) η = 60%, and (c) η = 80%. Numerical simulations (red dashed lines) of TOF transients (black markers) from deterministic hole transport model at 2V and 3V for (d) η = 40%, (e) η = 60%, and (f) η = 80%. (g) Table of hole transport coefficients, kinetic
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parameters, and material properties derived from fitting modeling predictions. Where Cdt = C0 exp(-Etn/kBT) and Etn is the trap energy depth.
Figure S6. A visual representation of the tunability of percolation in binary polymer nanoparticle glasses. Top: Simulated assemblies of binary nanoparticle glasses at η = 20%, 60%, and 80%. Bottom: The insulating nanoparticles, colored grey on top, are removed to reveal the percolation network of conducting nanoparticles colored blue on top and bottom. This demonstrates how the structure of a polymer percolation network can be tuned by simply varying η.
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