Fu-Ken Liu

Microwave Heating for the Preparation of Nanometer Gold Particles

In this paper we report a feasible method to synthesize gold nanoparticles with uniform size by microwave heating. In this work, a closed chamber of a microwave system with precise temperature control function was employed to synthesize the gold nanoparticles. Our data demonstrates that the temperature plays an important role in the synthesis of gold nanoparticles. With higher synthesis temperature, longer heating time duration and rapid gradient of temperature increase, the smaller diameter and the narrow size distribution of the gold nanoparticles were obtained. The concentrations of citrate represent the reductant in the synthesis reaction, which also influence the morphology of gold nanoparticles. The data demonstrates that gold nanoparticles with highly reproducible sizes could be synthesized by microwave heating.

Rapid fabrication of high quality self-assembled nanometer gold particles by spin coating method

This paper reports the fabrication of self-assembled gold nanoparticles attached to 3-aminopropyltrimethoxysilane (APTMS) modified fused silica substrates by the spin coating method. With the spin coating method, the gold nanoparticles can be fabricated on fused silica substrates with highly packing density in a short processing time. Our results clearly demonstrate that the spin coating method takes advantages of shorter fabrication time, higher uniformity, and better reproducibility when compared with the traditional immersion method.

Synthesis of Nanometer-Sized Poly (methyl methacrylate) Polymer Network by Gold Nanoparticle Template

Gold nanoparticle/polymer composites have been produced using a one-system polymer synthesis. The linear polymer, poly (methyl methacrylate) (PMMA, MW = 15,000 g/mol) is applied for the stabilization of gold nanoparticles. The Fourier transfer infrared (FT-IR) analysis data and transition electron microscopy (TEM) image reveal that the core shell structure of gold/PMMA nanocomposite has been synthesized. The ratio of the concentration of the capping polymer material to the concentration of the gold precursor could control the sizes of gold nanoparticles. With specific concentration of the reductant, the core-shell nanostructure could be fluctuated in order. After heating treatment, the network structure of PMMA capped gold nanoparticles could be synthesized as confirmed by the TEM image. The result indicates that PMMA not only acts as the stabilizer, but also as the bridge of the neighboring gold nanoparticles.

Rapidly Selective Growth of Nanoparticles by Electron-Beam and Optical Lithographies with Chemically Amplified Resists

Rapidly and precisely selective growth of self-assembled nanoparticles using an electron-beam or optical exposure system with commercial chemically amplified resists was demonstrated. The required exposure dosage was lessthan 10 μc/cm 2 for patterning chemically amplified resists. By immersing the patterned resist sample in the nanoparticle colloidal solution, nanoparticles were selectively self-assembled on the (3-aminopropyl)trimethoxysilane layer, which was partially covered by the patterned resist layer. The selective growth area can be performed from several hundred micrometers to sub-50 nm. This method has great potential to be used for rapidly selective growth of various nanoparticles or nanomaterials.

Combination with optical lithography and microwave rapid heating method for the selective-area synthesis of silver nanoparticles on silicon wafer

The ability to fabricate materials and structures with sub-micrometer scale features is interesting in many areas of science and technology [l]. Of importance for many applications in nanotechnology is the ability to arrange nanocrystals into larger-scale patterns with precise lateral control, such as photonic crystal, data storage, and biosensors. Recently, great efforts have also been made on position-controllable assembling of colloidal nanoparticles on solid substrates [2]. Despite the increasing efforts in the past few years, it is still a great challenge to develop an effective way to fabricate well-controllable nanostructures using colloidal as the structural elements.

Synthesis of silver nanorods by microwave irradiation

Microwave-assisted heating provides a rapid method for the preparation of silver nanorods due to its fast-heating characteristic. With these preliminary studies, we demonstrate the potential of the microwave rapid heating process for the synthesis of silver nanorods and nanowires.

Patterning of self-assembled nanoparticles by electron-beam lithography with chemically amplified resists

In this paper, patterning of self-assembled nanoparticles by using a shaped electron-beam exposure system with commercial chemically amplified resists (CAR) was demonstrated.

Highly effective chemical route for the preparation of uniform nanometer gold particles by microwave irradiation

Nanometer gold particles have received much attention as potentially useful materials showing novel electronic, optical, magnetic, and thermal properties derived from the quantum sized effect. Both size and shape of gold nanoparticles are evidence that affect properties of optical and electronic. Recently, thermal factor has been proven to have effects on the size distribution and uniformity of colloid-particles. The high thermal-treatment-rate and short sintering-time make microwave irradiation a promising method for obtaining nanostructured materials. To date, the preparation of nanometer gold particles by microwave irradiation has not been report yet, especially the discussion of the thermal effect on particle growth. In this work, the synthesis of gold nanoparticles by microwave irradiation with precise temperature controlled is studied.

Nanometer-size PMMA polymer network synthesis by gold nanoparticles template

In recent years, the interest in the synthesis and characterization of nanostructured materials has grown widely due to their distinctive physical and chemical properties. Recently, mono-dispersed nanoparticles protected by linear polymers were successfully synthesized of noble metal nanoparticles. Polymer protected, nano-size noble metals are receiving high attention, because they offer a high potential for many technological applications. In this study, the gold nanoparticles template was produced by chemical reduction of HAuCl/sub 4/ in the presence of NaBH/sub 4//PMMA (MW = 15,000 g/mol) reductant/stabilizer mixture media. Herein, the concentration of PMMA that affects the size and optical properties of gold particles is shown. The structure of PMMA/gold nanoparticles core shell was confirmed by TEM and FTIR.