pH sensor based on PDMS fiber doped by NaBaScSi2O7: Eu²⁺

In this study, a pH sensor based on PDMS fiber doped by $\mathrm {NaBaScSi_{2}O_{7}: Eu^{2}}^{+}$ was designed and manufactured. The no-core structured fiber sensor was prepared with fluorescent nanoparticles and silicone-based elastomers that enable both efficient excitation light delivery and fluorescence collection. Upon excitation at 395 nm, the phosphor $\mathrm {NaBaScSi_{2}O_{7}: Eu^{2}}^{+}$ exhibited strong green light peaking at 506 nm. Experimental results showed that the fluorescence intensity of the sensor decreased with the change of the solution in the range of pH 6.86-9.18, and the sensitivity of the sensor was 0.05 /pH. The pH sensor provided the possibility as a technology in biomedical detection and water quality survey and other aspects.