L. Štolcová1, R. Váňa2 and J. Proška1

1 Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Břehová 7, 115 19 Prague 1, Czech Republic2 TESCAN Brno, s r.o., Libušina třída 1, 623 00 Brno, Czech Republic

lucie.stolcova@fjfi.cvut.cz

Correlative SEM-SERS imaging of morphologically complex SERS-active substrates

Correlative RISE microscopy

The authors gratefully acknowledge the collaboration with the group of A. Kromka (IOP ASCR, v.v.i.) on the preparation of nanocorals and thank M. Petrenec (TESCAN-ORSAY HOLDING) for their characterization using FIB-SEM. This work was supported by the Czech Science Foundation grant No. P205/13/20110S.

100 nm

+ =

SERS mapping of ‘nanocorals‘

Correlative Raman Imaging - Scanning Electron microscopy- Directly links ultra-structural surface properties to molecular compound information - Uncompromised resolution

Scannig electron microscope MAIA (TESCAN) • Resolution 1.4 nm at 1 kV• Can be equipped with FIB (focused ion beam)

Confocal Raman imaging microscope alpha300 (WITec)• Resolution 200 - 300 nm • Ultra-fast imaging (integration times down to < 1 ms)

Correlative RISE microscopy applications in SERSImaging SERS ‘hot spots‘ in 3D

• Studies of structure-function relationship

• Hot spots imaging

• Comparing ultra-structural surface properties of SERS substrates before and after Raman measurements

Revealing substrate damage induced by SERS measurements

200 nm

FIB

Correlating structure to function

1 mm

Melted polystyrene templates in FON observed after SERS measurement

Confocal Raman imaging - z scan

5 mm

SERS intensity map: 4-mercaptopyridine (integrated intensity of 1215 cm-1 peak)

SEM image of the same area of silver nanocoral array Image overlay

SERS intensity map: rhodamine 6G (integrated intensity of 1510 cm-1 peak)

SERS signal distribution on ‘nanocorals‘ appears to be very homogenousbut SEM characterization suggests major role of tips and nanogaps in the Raman signal enhancement.

How can we determine the origin of the enhancement on such complex nanostructures?

Variation in SERS intensity distribution with depth:

ICAVS 8 student grant awarded

1 mm

SEM image of one nanocoral Nanocoral array (red circles represent laser spots during SERS mapping)

SERS spectra of 4-aminothiophenol obtained by spectral mapping of a nanocoral array

SH

NH 2

Correlative Raman - SEM imaging reveals the enhancement distribution of silver-coated glass fibres.The highest SERS intensity regions are located:

» along the edges of the deposited silver layer » at fibre crossings

Acknowledgement

[1] J. Jiruše et al., J. Vac. Sci. Technol. B 32, 06FC03 (2014).[2] O. Hollricher et al., Microscopy Today 22, 36-39 (2014).[3] L. Štolcová, et al., PIERS Proceedings, Stockholm, Sweden, Aug. 12-15, 426-430 (2013).

References

Gold film over nanosphere (FON) SERS substrate

10-10 M, 30 min

10-6 M, 30 min