Up-Conversion Luminescence and Optical Temperature Sensing Behaviour of Y[sub.2]O[sub.3]:Ho[sup.3+], Yb[sup.3+] Phosphors

• Published in: Crystals (Basel) 2023-08, Vol.13 (8)
• Main Authors: Makumbane, Vhahangwele, Yagoub, Mubarak Y. A, Xia, Zhiguo, Kroon, Robin E, Swart, Hendrik C
• Format: Article
• Language: English
• ISSN: 2073-4352; 2073-4352
• DOI: 10.3390/cryst13081288

The up-conversion (UC) and temperature sensing behaviours of Y[sub.2]O[sub.3]:Ho[sup.3+], Yb[sup.3+] phosphors were investigated. A series of Y[sub.2]O[sub.3]:Ho[sup.3+], Yb[sup.3+] phosphors were synthesized using a solution combustion method. The cubic structure of the Y[sub.2]O[sub.3] with an Ia3¯ space group was analysed by using X-ray powder diffraction. Scanning electron microscopy was conducted to study the surface morphologies of the UC phosphors. Under 980 nm excitation, the UC emissions of Ho[sup.3+] from the [sup.5]S[sub.2] → [sup.5]I[sub.8], [sup.5]F[sub.5] → [sup.5]I[sub.8] and [sup.5]S[sub.2] → [sup.5]I[sub.7] transitions were observed, which occurred through UC energy transfer (ET) processes. The Yb[sup.3+] ion concentration severely affected the UC emission. The sensing behaviour of the phosphor was investigated through the green ([sup.5]F[sub.4], [sup.5]S[sub.2] → [sup.5]I[sub.8]) to red ([sup.5]F[sub.5] → [sup.5]I[sub.8]) fluorescence intensity ratio (FIR). The maximum absolute and relative sensitivity values of S[sub.A] = 0.08 K[sup.−1] and S[sub.R] = 0.64% K[sup.−1] were obtained. The results revealed that the prepared Y[sub.2]O[sub.3]:Ho[sup.3+], Yb[sup.3+] phosphor is suitable for optical sensing at high temperatures.