Microemulsion-Based Synthesis of Highly Efficient Ag-Doped Fibrous SiO 2 -TiO 2 Photoanodes for Photoelectrochemical Water Splitting.

Fibrous SiO₂-TiO₂ (FST) is one of the most promising materials for advancing photoelectrochemical water-splitting technology due to its cost-effectiveness and environmental friendliness. However, FST faces intrinsic limitations, including its low conductivity and wide bandgap. In this study, significant progress was made in modifying FST to overcome some of these limitations. This work involved synthesizing a new photoanode made of Ag-doped FST utilizing the microemulsion process. The Ag-doped FST was characterized using XRD, FTIR, UV–Vis, DRS, N₂ adsorption–desorption, FESEM, TEM, and XPS. The results confirmed the formation of a continuous concentric lamellar structure with a large surface area. The addition of Ag species into the FST matrix caused interactions that reduced the bandgap. The Ag-doped FST photoanode exhibited an impressive photocurrent density of 13.98 mA/cm² at 1.2 V (vs. RHE). This photocurrent density was notably higher than that of FST photoanodes, which was 11.65 mA/cm² at 1.2 V (vs. RHE). Furthermore, the conduction band of Ag-doped FST is positioned closer to the reduction potential of hydrogen compared to that of FST, SiO₂, and TiO₂, facilitating rapid charge transfer and enabling the spontaneous generation of H₂. The fabrication of Ag-doped FST provides valuable insights into the development of high-performance photoanodes for PEC water splitting. [ABSTRACT FROM AUTHOR]