Bifunctional properties of manganese-doped tin oxide nanostructures for visible light–driven photocatalytic activity and antibacterial applications

In this study, a simple chemical co-precipitation method was employed for the synthesis of pure SnO₂ alongside various Mn concentrations, with subsequent characterization conducted using a suite of analytical techniques. Powder X-ray diffraction (XRD) analysis unveiled the rutile tetragonal structure of SnO₂, with a space group identified as P4₂/mnm. The average crystallite size, determined across the synthesized pure and doped samples, ranged from 31 to 21 nm. Photoluminescence (PL) spectra revealed emissions attributed to defect states, exhibiting decreased intensities. Optical band gap values, indicative of electronic properties, were observed to vary from 3.62 to 3.09 eV, correlating with the Mn concentration increase. X-ray photoelectron spectroscopy (XPS) provided detailed information on the binding energy values of Sn3d, O1s, and Mn2p orbitals. Notably, Mn-doped samples exhibited enhanced photocatalytic activity under visible light irradiation compared to pure SnO₂. Furthermore, antibacterial assays demonstrated significant antibacterial efficacy against Escherichia coli bacteria for Mn-SnO₂ nanoparticles. These findings underscore the promising potential of Mn-doped SnO₂ nanostructures for various applications, warranting further investigation and exploration.