## 3 Artificial Intervention in the Degradation of Antibiotics
### New Type of Catalyst
#### 3.5.1 Nano Photocatalyst  
Catalysts such as TiO2, ZnO, and g-C3N4 significantly enhance the efficiency of photocatalytic degradation by facilitating the effective separation of photogenerated electron-hole pairs and increasing the number of active surface sites. For instance, [PERSON] [117] prepared ZnO/TiO2 heterojunction nanofilms using a magnetron sputtering method, employing a stepwise annealing strategy. The ZnO layer was annealed for 3 h, while the TiO2 layer was annealed for 2 h to optimize various physical and chemical properties, including the film lattice orientation, oxygen vacancy concentration, and specific surface area. This approach achieved efficient degradation rates of ofloxacin (OFX, 99.5%), tetracycline (TC, 77.6%), and rhodamine B (RhB, 94.1%), thereby enhancing the photocatalytic degradation efficiency of these pollutants. Additionally, doping with elements such as nitrogen or carbon, or constructing heterojunctions like TiO2/g-C3N4, can broaden the light response range, enhance the charge separation efficiency, and synergistically improve the degradation performance, thereby increasing the overall degradation efficiency. For example, the synthesis of La-doped TiO2@g-C3N4 composite photocatalysts enables g-C3N4 to be excited by visible light (Eg = 2.66 eV), resulting in the generation of electrons (e\({}^{-}\)) and holes (h\({}^{+}\)). The electrons then transfer to the conduction band (CB) of TiO2 through La bridges, while the generated reactive species, including -O2\({}^{-}\), SO4\({}^{-}\), \(\bullet\)OH, h\({}^{+}\), and e\({}^{-}\), collaborate to attack TCH molecules, ultimately mineralizing them into CO2 and H2O [118].  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Catalyst Type** & **Representative Materials** & **Degradation Mechanism** & **Advantages** & **Limitations** \\ \hline \multirow{10}{*}{Nanoph photocatalysts} & & Efficient separation of & & \\  & & photogenerated electron–hole & & \\  & & pairs and increased surface & & \\  & & active sites. & & \\  & TiO2, & Heterojunctions & & \\  & ZnO, & (e.g., ZnO/TiO2) enhance & & \\  & g-C3N4 & charge separation; & & \\  & doping (N, C) broadens light & & & \\  & & absorption range and & & \\  & & improves charge & & \\  & & separation efficiency. & & \\ \hline \multirow{10}{*}{MOFs} & & Adsorption (electrostatic, \(\pi\)-\(\pi\), & Ultra-high specific & Poor water stability \\  & MIL101(Fe), ZIP-8, & hydrophobic, acid–base & surface area (strong & (some MOFs are prone \\  & UiO-66 & & interactions); & adsorption capacity); & \\  & & photocatalytic generation of & & \\  & radicals (e.g., O2\({}^{-}\) and \(\bullet\)OH) & & & \\  & & for pollutant degradation. & & \\  & & & active sites. & \\ \hline \multirow{10}{*}{Carbon-based Single-Atom Catalyst} & & Single-atom metals (e.g., Ba & Atomic-level utilization & Complex preparation \\  & Ba/g-C3N4, & and Co) optimize carrier band & (100\%); & \\ \cline{1-1}  & Ag/mpg-C3N4 & structure (e.g., g-C3N4) to & significantly improved & \\ \cline{1-1}  & & enhance light absorption. & reaction kinetics. & \\ \hline \hline \end{tabular}
\end{table}
Table 3: A summary of the new catalysts.