(169c) Synthesis of Egyptian Blue and Mechanisms

Calcium copper silicate (CaCuSi₄O₁₀), known as Egyptian Blue (EB), is a pigment that exhibits a strong near-infrared (NIR) (910 nm) fluorescent emission when exposed to a strong visible light source.This property makes it a novel candidate for use as a basis for nanomaterial-based sensors in surface water, as its IR signal is very strong in comparison with current commonly used IR reporters. Also, IR signals penetrate biological samples better, and are scattered less than visible range signals. Since the goal of the research is to produce a uniform coating of Egyptian Blue nanoparticles, first the synthesis must be controlled to obtain a uniform morphology. The reaction conditions for Egyptian Blue synthesis were explored with thermogravimetric analysis coupled with mass spectrometry, and high temperature X-ray diffraction (HT-XRD) measurements in order to better understand the reaction mechanism. A reproducible maximum in EB yield was observed around 7 °C/min in the HT-XRD analyses. Here we report the reaction conditions, the yields, and the photoluminescence characterization of the synthesized EB samples.