Gold islands

Campbell reported that propylene adsorbs weakly on gold surfaces and adsorbs moderately on T1O2 (11 0) with a desorption activation energy of 11.3kcal/mol and that propylene adsorbs most strongly at the perimeter of gold islands on Ti02 (11 0) [68]. 

Figure 5.11 STM image of a growing Pd monolayer, which had nucleated on Au(l 1 1) at the rim of a gold island. Although practically equal in height, the Pd layer appears brighter than the gold island in the center. (Reproduced with permission from Ref. [49].)...

Naohara etal. [434] have also studied electrodeposition of Pd from PdCfi " complex on Au(lOO) electrode using in situ STM. Electrochemical deposition of Pd on Au(lOO) occurred at potentials more negative than 1.0 V. The first Pd layer was deposited not only on the terrace but also on gold islands, which were formed as a result of the lifting process... 

Figure 16.20. Micro-SERS spectra of FA films cast from solutions at (a) pH 5, (b) pH 8, and (c) pH 11 on 9-nm gold island films. Laser excitation at 785 nm and spectra were collected from different spots as marked on the optical image. Reprinted from Alvarez-Puebla et al. (2004).

Speets, E.A., Ravoo, B.J., Roesthius, F.J.G., Vroegindeweij, F, Blank, D.H.A and Reinhoudt, D.N. (2004) Fabrication of arrays of gold islands on self-assembled monolayers using pulsed laser deposition through nanosieves, Nano Lett. 4 841-844. 

Meriaudeau F, Wig A, Passian A et al (2000) Gold island fiber optical sensor for refractive index sensing. Sensors Actuators B Chem 69 51057... 

These co-mercaptoalkyl carboxylic acids were selectively adsorbed from ethanol solution (1 mmol L-1) only on the gold dots which were laterally deposited in the first step on the silicon wafer. Imaging-XPS analysis revealed the success of the laterally controlled adsorption of the tu-mercaptoalkyl carboxylic acids which can only be seen on areas coated by gold islands and not on the silica bars in between (Fig. 11). 

Fig. 11 Laterally gold structured silicon wafer to control the spatial adsorption of PVFA-co-PVAm (a) photograph of the gold structured silicon wafer (genuine size of the gold islands 45 pm by 45 pm), (b) spatially resolved XPS image of the lateral gold layer (the Au 4f peak is depicted in black whilst the peaks of O 1 s and Si 2p are pale), (c) spatially resolved XPS image of 11-mercaptoundecanoic acid adsorbed on the laterally structured gold layer (the S 2p peak is depicted in white whilst Si 2p is dark)...

Fig. 1.48. Absorption spectra of small gold clusters Au2, Au4, Aug, and Au2o in comparison to the spectra of gold atoms (lower left frame) and nanometer size gold islands (upper right frame). AU spectra were obtained with the cavity ring-down method. The mass-selected clusters were soft-landed onto an a-Si02 substrate. The gold nanoparticles were grown on the same substrate by thermal evaporation...

Murray investigated the effect of gold layers deposited on silver island films on the SERS of cyanide. Gold island films did not support SERS of cyanide (within the detection limit of about... 

Figure 7.10 AFM images of an electrolessly deposited gold island on SAM 5 (THF) using citrate-NP as seeds.

We are currently in the process of determining the electrical properties of the gold islands deposited onto the SAMs to make sure that neither the pCP process nor the ELD chemistry results in destruction of the monlayers or the formation of shorts. Promising results have already been obtained in collaboration with WdlTs group in Bochum, which will be reported elsewhere. 

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