Modification of Silicon Surface with Silver, Gold and Palladium Nanostructures via Galvanic Substitution in DMSO and DMF Solutions

Advances in Materials Science and Engineering

Кuntyi

Nichkalo

et al. 2019

Self Cite

The process of gold nanoparticle (AuNP) precipitation on the silicon (Si) surface by galvanic replacement (GR) in dimethyl sulfoxide (DMSO) solution depending on the concentration of H[AuCl4], temperature, and duration was investigated. It is established that with an increase in the concentration of [AuCl4]− ions (from 2 to 8 mM H[AuCl4]), both the size of AuNPs and their surface coverage density are increased. It is demonstrated that an increase in temperature causes the size of AuNPs to increase from 40 to 80 nm at 40°C to 80–120 and 120–160 nm at 50 and 60°C, respectively. As the duration of the GR process increases, there is a tendency of the particle size growth. Under the studied deposition conditions, the organic aprotic solvent medium contributes to the formation of spherical AuNPs with 2D substrate filling. It is established that the AuNPs deposited on the silicon surface catalyze the process of metal-assisted chemical etching (MacEtch), which makes it possible to obtain Si nanostructures in the form of nanowire arrays.

Section: Introductionmentioning

confidence: 74%

Section: Auclmentioning

confidence: 99%

Deposition of Gold Nanoparticles via Galvanic Replacement in DMSO and Their Influence on Formation of Silicon Nanostructures

Advances in Materials Science and Engineering

Кuntyi

Nichkalo

et al. 2019

Self Cite

“…2, d), the adsorption of DMSO molecules with gold nanoparticles is reduced. In other words, the deterrent effect of surface complexes on the size growth of Au nanoparticles decreases [16], which results in an increase in their size and therefore the growth of Au nanofilm the morphology of which becomes discontinuous. Thus, the size dependence of deposited nanoparticles on temperature is linear in the range 50 -70 °C (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…In contrast, utilizing the galvanic repalcement in the medium of organic aprotic solvents, e.g. DMSO can prevent the occurrence of these disadvantages, as it was shown in [15,16].…”

Section: Introductionmentioning

confidence: 99%

Optimal Conditions for the Deposition of Gold Nanofilms on a Silicon by Galvanic Replacement Method

Nichkalo

Chekaylo

2019

PCSS

The formation conditions of gold nanofilms on silicon (Si) substrate by galvanic replacement in a dimethyl sulfoxide (DMSO) solvent and their subsequent use for the fabrication of Si nanostructures by metal-assisted chemical etching (MACE) method were under study. It was found that the average size and number of Au nanoparticles increase with an increase in the reducible metal ion concentration from 2 to 8 mM HAuCl 4 in DMSO, whereas the distribution of Au nanoparticles in height remains low for all concentrations of the reducible metal. In the temperature range 40 -70°C, a different morphology of the deposited Au nanofilms observed. In particular, at 40 °C, the film is porous mainly homogeneous, whereas at a temperature of 50°C the film is rougher. The subsequent rise in temperature from 60°C to 70°C results in the formation of Au nanofilm with a discontinuous morphology. It was established that regardless of the morphology of deposited Au nanofilms, the Si nanostructures maintain a vertical orientation to the plane of the Si substrate during MACE-etching. The produced Si nanostructures were 1.5 -2.5 μm in height and their average diameter ranged from 100 to 300 nm.

“…Reaction (5) results in the passivation of the silicon surface. To prevent such undesirable processes, a nonaqueous medium may be used as it was shown previously in [29][30][31][32], where the deposition of metals on silicon was performed in organic solvents. However, these papers report about the deposition of noble metals via the galvanic replacement method.…”

Section: Introductionmentioning

confidence: 99%

Pulse Electrodeposition of Palladium Nanoparticles onto Silicon in DMSO

Кuntyi

Dobrovetska

et al. 2019

Journal of Chemistry

Self Cite

The deposition of palladium nanoparticles (PdNPs) on the surface of n-Si (100) substrate by pulsed electrolysis in dimethyl sulfoxide (DMSO) solutions of Pd(NO3)2 was investigated. It has been shown that nonaqueous medium (DMSO) contributes the Pd (II) recovery at high cathode potential values avoiding side processes to occur. In combination with the pulse mode, this allows the deposition of spherical PdNPs with their uniform distribution on the silicon surface. We established that the main factors influencing the geometry of PdNPs are the value of the cathode potential, the concentration of palladium ions in solution, and the number of pulse-pause cycles. It is shown that with increasing Ecathode value there is a tendency to increase the density of silicon surface filling with nanoparticles. As the concentration of Pd(NO3)2 increases from 1 to 6 mM, the density of silicon surface filling with PdNPs and their average size also increase. We found that with increasing the number of pulse-pause cycles, there is a predominant growth of nanoparticles in diameter, which causes 2D filling of the substrate surface.