Resistance of Single Ag Nanowire Junctions and Their … of Single Ag Nanowire Junctions and Their...

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Transcript of Resistance of Single Ag Nanowire Junctions and Their … of Single Ag Nanowire Junctions and Their...

Resistance of Single Ag Nanowire Junctions and

Their Role in the Conductivity of Nanowire

Networks

Allen T. Bellew*, Hugh G. Manning, Claudia Gomes Da Rocha, Mauro S. Ferreira, & John

J. Boland

Supporting Information

S1 Length and diameter statistics of nanowires

Figure S1.1 Length (a) and diameter (b) statistics of nanowires used to fabricate networks

which formed the basis of modelling analysis.

S2 TEM Characterisation of Ag Nanowires

Figure S2.1 TEM image of two crossed Ag nanowires, showing the thin PVP layer that coats

the nanowires in their native state.

S3 Resistivity of Ag Nanowires

Figure S3.1 Plot of nanowire resistivity as a function of diameter. There is no clear

dependence on nanowire diameter in the measured range.

S4 SEM analysis of Ag nanowire junctions.

Figure S4.1 SEM analysis of furnace annealed junctions. Evidence of nanowire

melting/welding is visible in panels b, c, e, f, and g.

Figure S4.2 SEM analysis of hotplate annealed junctions.

Figure S4.3 SEM analysis of electroformed junctions.

S5 Dependence of Junction Resistance on Junction Area

To determine whether the junction resistance shows a dependency on the diameter of the

constituent nanowires, an estimate of the maximum junction area was calculated. Given the

pentagonal nature of the nanowires, the maximum area of any junction can be considered as

the product of the side length of each nanowire. Here it is assumed that each nanowire is a

regular pentagon shape, and that the measured radius, r, of the nanowire is equivalent to the

inradius of the pentagon. Based on this, the side length is then:

� = �2 ∙ tan

1805 �

The angle of the junction, θ, was measured and the area then calculated according to the

equation:

���� = �� ⋅ ������

where a1 and a2 are the side lengths of nanowires 1 and 2, respectively, that comprise the

junction.

S6 Stick-model images of networks appearing in Table 1

Figure S6.1 Stick-model images of networks appearing in Table 1. Networks are labelled 1-6

as they appear in Table 2 of the main text. All images are shown at the same scale. Scale bar

is 2 µm.