Sintering-Based In-Situ Synthesis and Characterization by TEM of Noble Metal Nanoparticles for Ceramic Glaze Color...

Area of Science:

• Materials Science
• Nanotechnology
• Ceramic Engineering

Background:

• Gold nanoparticles (NPs) produce red pigments in ceramics, but NP size limits color range.
• Controlling nanoparticle size and composition is key to expanding color palettes.

Purpose of the Study:

• To develop a method for achieving a wide spectrum of colors in ceramic glazes using gold and silver nanoparticles (NPs).
• To explore the effect of gold-to-silver salt ratios on NP development and resulting colors.
• To investigate NP stability and color performance in different firing atmospheres.

Main Methods:

• Incorporation of gold and silver salt mixtures into ceramic glazes.
• Sintering glazes under controlled oxidative and reductive firing atmospheres.
• Analysis of color performance using reflectance spectrometry.
• Characterization of nanoparticle composition and size using transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS).

Main Results:

• Altering gold-to-silver salt ratios enabled color control from red to green.
• Reductive firing atmospheres successfully formed and sustained mixtures of gold and silver NPs.
• Oxidative atmospheres were unsuitable for silver NP stability.
• Achieved nontoxic, low metal loading color systems.

Conclusions:

• Noble metal NP ratio blends offer a new pathway for controlled, low-loading ceramic coloration.
• Reductive firing is essential for stable gold-silver NP formation in glazes.
• This technique expands the color palette beyond traditional red pigments.