## 4 Conclusions  
The melt quenching method was used to synthesize four compositional systems--PbO\({}_{2}\)-SiO\({}_{2}\), PbO\({}_{2}\)-SiO\({}_{2}\)-CeO\({}_{2}\), PbO\({}_{2}\)-SiO\({}_{2}\)-Eu\({}_{2}\)O\({}_{3}\), and PbO\({}_{2}\)-SiO\({}_{2}\)-Yb\({}_{2}\)O\({}_{3}\)--coded as PS, PSC, PSE, and PSY. The effect of gradually reducing the PbO\({}_{2}\) content in the glass network on the physical and radiation shielding properties has been amply investigated. We found that the density decreases with increasing SiO\({}_{2}\) concentration and slowly increases with RE content. The V\({}_{\rm m}\) decreases and the OPD increases for all glass systems. V\({}_{\rm o}\) shows opposite behavior compared to OPD. The incorporation of rare earth elements improves the radiation attenuation properties, quantified by parameters like the mass attenuation coefficient, the linear attenuation coefficient, the half-value layer, and the mean free path. Among the tested compositions, PSY exhibited the highest shielding efficiency, driven by superior density and enhanced photon interaction. Increasing the SiO\({}_{2}\) content in the lead host matrix gradually shifted the absorption edge to lower wavelengths, increased the optical band gap energy, and reduced the Urbach energy up to sample PS5. Using ultraviolet excitation, Pb\({}^{2+}\) ions exhibit emission bands that vary from ultraviolet to deep red regions; their intensity depends on the PbO\({}_{2}\) content and significantly influences the  
Figure 11: CIE 1931 diagram with the color coordinates of the PS glass samples. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{2}{c}{**Color Coordinates**} & \multirow{2}{*}{**Ldom**} & \multirow{2}{*}{**CRI**} & \multirow{2}{*}{**LER**} & \multirow{2}{*}{**CCT**} & \multirow{2}{*}{**CP**} \\  & \(\mathbf{x}\) & \(\mathbf{y}\) & [nm] & [\%] & [Im/W] & [K] & [\%] \\ \hline PS 0 & 0.2957 & 0.3333 & 491.7 & 92 & 227 & 7411 & 12.7 \\ \hline PS 1 & 0.3039 & 0.3468 & 497.7 & 91 & 235 & 6812 & 9.2 \\ \hline PS 2 & 0.2978 & 0.335 & 492.3 & 93 & 227 & 7267 & 11.9 \\ \hline PS 3 & 0.2911 & 0.3232 & 488.6 & 94 & 217 & 7874 & 15 \\ \hline PS 4 & 0.285 & 0.3132 & 486.2 & 95 & 204 & 8557 & 17.9 \\ \hline PS 5 & 0.2897 & 0.3161 & 486.5 & 95 & 198 & 8129 & 16.1 \\ \hline PS 6 & 0.2924 & 0.3225 & 488.3 & 94 & 202 & 7803 & 14.6 \\ \hline PS 7 & 0.2881 & 0.3155 & 486.5 & 95 & 198 & 8260 & 16.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Color parameters of the PS glass system. color coordinates and the color parameters. Samples PS0-PS3 revealed semiconducting behavior and may be a promising host matrix for solar cells and w-LED applications. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app15020864/s1](https://www.mdpi.com/article/10.3390/app15020864/s1)]([https://www.mdpi.com/article/10.3390/app15020864/s1](https://www.mdpi.com/article/10.3390/app15020864/s1)), Figure S1: Variation of OPD and Vo as a function of glasses composition for the: (a) PS; (b) PSC; (c) PSE; and (d) PSY systems. Conceptualization, M.Z. ; methodology, M.Z. ; validation, M.Z. and V.R. ; investigation, M.Z. and R.-C.S. ; data curation, M.Z. ; writing--original draft preparation, M.Z. and R.C.G. ; writing--review and editing, M.Z., R.C.G. and V.R. ; visualization, M.Z., R.-C.S., R.C.G. and V.R. ; supervision, M.Z. and V.R. ; project administration, M.Z. and V.R. ; funding acquisition, M.Z. and V.R. All authors have read and agreed to the published version of the manuscript. This research was funded by the Ministry of Research, Innovation and Digitization through CNCS-UEFISCDI, project No. PN-III-P1-1.1-PD-2021-0721, within PNCDI III, and through the Nucleu Programme within the National Plan for Research Development and Innovation 2022-2027, carried out with the support of MCID, Project No. PN 23 24 02 01. Not applicable. The data presented in this study are available on request from the corresponding author. The authors declare no conflicts of interest.