Particle Size Control of Y₂O₃:Eu³⁺ Prepared via a Coconut Water-Assisted Sol-Gel Method

Table 1

Crystallite size of the Y₂O₃:Eu³⁺-particles produced by proteic sol-gel as a function of pH and temperature (n.d. stands for not determined).

	Without pH control	pH = 5.0	pH = 7.0	pH = 9.0
T = 350°C	amorphous	amorphous	3 nm	amorphous
T = 400°C	amorphous	amorphous	4 nm	6 nm
T = 450°C	7 nm	7 nm	5 nm	7 nm
T = 500°C	9 nm	9 nm	18 nm	n.d.
T = 850°C	50 nm	n.d.	n.d.	n.d.