PELCO^® Gold Nanoarrays

Nanoparticles serve as significant research tools in better understanding and unraveling the mysteries embodied in nanotechnology research. Colloidal gold particles, in particular, are both excellent catalysts for nanowire growth of a variety of materials and active sites for SERS (surface enhanced Raman scattering). The colloidal gold particles are applied with a proprietary process and baked in air at 250°C to create high purity gold particles secured on the substrate.

The line of PELCO^® Gold Nanoarrays are unique products that provide:

• Substrate particle densities suited to SERS or material growth
• A choice of available substrates
• Excellent batch size uniformity and uniform particle distribution
• Highly stable products

Figure 1: SEM image of a 15nm PELCO® Normal Density Gold Nanoarray. The histogram to the right shows the size distribution, mean and standard deviation for the array.

Uniform and regular coverage of nanoparticles is highly desirable for systematic and reproducible results. Ordered arrays are ideal. PELCO^® Gold Nanoarrays overcome the problems associated with other methods:

• The high cost of electron beam lithography
• The random dispersion from adsorption or evaporative colloid deposition

Figure 2: SERS – AFM image of an isolated carbon nanotube on a PELCO® Gold Nanoarray (30nm Au on glass). The Raman spectrum was measured at 1mW with a 25mW HeNe (633nm) laser. Courtesy of Steve Cronin, USC.

The PELCO^® Gold Nanoarrays are available on a number of substrates:

• Glass: 5 x 10mm
• Quartz: 5 x 10mm
• Silicon: 5 x 10mm

The gold nanoparticles have the following characteristics:

• 15 or 30nm average particle diameter
• Excellent uniformity and particle distribution
• Normal density coating for material growth (Figure 1)
• High density coating for SERS (Figures 2 and 3)

Figure 3: SEM image of a PELCO® array demonstrating high density coverage for 30nm gold particles on a quartz substrate. The characteristic plasmon resonance absorption curve, is shown on the right. The Histogram, below, is indicating the particle size distribution of the array.

Figure 4: ZnO nanowires grown using a PELCO® Gold Nanoarray (gold nanoparticles on a quartz substrate) [1,2] 1. Geng, C. et al., 2004. Adv. Funct. Mater. 2004, 14:589-594. 2. Huang, et al, 2001. Adv. Mater., 13:113-116.