## 4 Conclusions  
In this research, nanoparticles of ZnBi\({}_{2}\)O\({}_{4}\) have successfully been synthesized by co-precipitation and then described by different methods to distinguish the optical, dielectric, and electrochemical properties. Firstly, DRX and FTIR were used to confirm the obtaining of the spinal phase. Then, an SEM analysis was performed to investigate the morphology of the nanoparticles ZBO; uniform shapes have been observed. An optical study was done to investigate ZBO optical and dielectric proprieties, which shows that this catalyst has good photocatalytic activity in the UV region with a gap band (-2.8 eV). Additionally, electrochemical characterizations were investigated in order to determine the type of catalyst, define the energetic diagram, and determine the location of the conduction and valence bands. An \(n\)-type semiconductor with a flat band potential of 0.54 V\({}_{\mathrm{SCE}}\) was discovered. The activity of this prepared photocatalyst was then checked for photodegradation of the Cefixime antibiotic under various light sources to demonstrate the finding of the optical characterization. The results revealed that the ZBO catalyst could lead to 89% of CFX degradation under solar light in only 30 min and 88% under UV irradiation after 2 h. Those results indicate that the catalyst can be a modern catalyst candidate for the removal of organic contaminants in water under solar radiation. We conclude with an outlook on future research, since this catalyst has demonstrated strong photocatalytic properties. It will be tested for the inactivation of bacteria and other microorganisms.  
Figure 10: Energy diagram and suggested mechanism for CFX degradation by ZBO nanoparticles.  
**Supplementary Materials:** The following are available online at [[https://www.mdpi.com/article/10.3390/app11093975/s1](https://www.mdpi.com/article/10.3390/app11093975/s1)]([https://www.mdpi.com/article/10.3390/app11093975/s1](https://www.mdpi.com/article/10.3390/app11093975/s1)), Figure. S1 Chemical formula of the antibiotic Cefiixime, Figure. S2 UV-visible spectra of Cefixime (10 mg/L), Figure. S3 UV-visible spectrum of ZnBi\({}_{2}\)O\({}_{4}\), Figure. S4 Spectral distribution of n (\(\lambda\)) and K (\(\lambda\)), Figure. S5 Variation of SELF and VELF as a function of the energy (hv), Figure. S6 \(\epsilon\)_r_ as function of \(\lambda\)^2, Figure. S7 Variation of the real and imaginary parts of the optical conductivity as a function of the energy (hv), Figure. S8 Semi-logarithmic plot over ZnBi\({}_{2}\)O\({}_{4}\) electrode, Figure. S9 Bode plan (log Z vs. log frequency)[PERSON]  
**Author Contributions:** Conceptualization, O.B. and H.K.; methodology, A.A.; software, O.B.; validation, A.A.A. ([PERSON]) and A.A.; formal analysis[PERSON] M.T.; investigation, O.B.; resources, N.N.; data curation, O.B.; writing--original draft preparation, O.B., A.A.A. ([PERSON]) and A.A.; writing--review and editing, O.B., A.A.A.A ([PERSON]) and A.A.; visualization, A.A.A. ([PERSON]) and M.A.; supervision, A.A.A. ([PERSON]) and A.A.; All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Not applicable[PERSON]  
**Acknowledgments:** This work was financially supported by both the Faculties of Mechanical Engineering and Process Engineering and Chemistry[PERSON]  
**Conflicts of Interest:** The authors declare that they have no conflict of interest.