Copyright WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, Particle. Particle Systems Characterization. Supporting Information

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1 Copyright WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, Particle Particle Systems Characterization Supporting Information for Part. Part. Syst. Charact., DOI: /ppsc Manipulating the Morphology of Silver Nanoparticles with Local Plasmon-Mediated Control Andreas Polywka, Anna Vereshchaeva, Thomas Riedl, and Patrick Görrn*

2 Copyright WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, Supporting Information for Part. Part. Sys. Charact., DOI: /ppsc.( ) Manipulating the Morphology of Silver Nanoparticles with Local Plasmon Mediated Control Andreas Polywka, Anna Vereshchaeva, Thomas Riedl, and Patrick Görrn* 1

3 Figure S1. The influence of thermal annealing. A sample formerly developed in humid air (gray) is thermally annealed. After annealing (red) a V-like shape of the spectral transmission is found similar to the transmission spectra of pristine samples (before development in humid air). Thermal annealing has therefore the opposite effect as the reported development process. 2

4 Figure S2. The influence of the atmosphere. Dry air in the same way as pure nitrogen has no effect on the transmittance of the film, while humid air causes the described development. Taken together, this unambiguously identifies water as origin of the development process (a). The development in humid air can even be interrupted by a change of atmosphere and can be continued later on (b). 3

5 Figure S3. Water drop on silver island film. A water drop is placed on top of a pristine film (a). After the drop has evaporated, the sample develops over the entire area (note the color change). In the area formerly covered by water the transmission increase is extraordinary high confirming that water causes the development. 4

6 Figure S4. The influence of the self-assembled monolayer (MPTMS ((3-mercaptopropyl)- trimethoxy-silane)) as adhesion promoter. The films on pristine PDMS show the reported sensitivity to moisture (a). A film deposited in the same process but on top of PDMS treated with MPTMS shows no change in humid air within the same period of time (3.5 hours) (b). 5

7 Figure S5. Visible light exposure causes increased adhesion. A sample exposed through an exposure mask in the same way as described in Figure 1, is not exposed to humidity and therefore not developed. Instead it is stored in liquid isopropanol and placed into an ultrasonic bath. The Figure shows the sample in isopropanol after 0 min (a), 11 min (b), 36 min (c), 73 min (d), 88 min (e) and 115 min (f). In the unexposed area, the silver particles are removed while in the exposed area the particles remain on the PDMS foil which indicates that the light exposure increases the local adhesion of the particles. 6

8 Figure S6. Atomic force micrograph (surface topography) of the transition between exposed (left) and unexposed area (right) of a developed sample. Note, the silver on the right side has not been removed during development, only the roughness was significantly decreased due to the coalescence of the silver particles. 7

9 Figure S7. Fine tuning of the optical properties. During light exposure, a cover plate is slowly moved in front of the sample, using a stepping motor. Thereby, a continuous variation of the light dose is achieved as the left part is exposed for a long time (color stays like in pristine samples) while the right part is only shortly exposed to light (color is changed during development). 8

10 Figure S8. Proof of concept for the transfer-printing of the generated patterns. A patterned sample is prepared using the inverse exposure mask as in Figures 1 and S5 on top of PDMS. A thin epoxy film is placed on the upper half of the smiley image (a). After curing, the epoxy film is carefully removed from the PDMS substrate (b, c). Thereafter, the silver completely adheres to the epoxy film. The PDMS surface on this upper area remains intact, only the silver is transferred. 9