Synthesis of PbO–TiO 2 Nanocomposites for Advanced Photocatalytic and Antimicrobial Applications

ABSTRACT PbO‐TiO 2 nanocomposites were synthesized via hydrothermal route to overcome the limitations of pristine TiO 2 photocatalysts, including poor visible‐light activation, and rapid charge recombination. Composites with varying PbO:TiO 2 ratios (25:75 and 50:50) were prepared using titanium (IV) butoxide and lead nitrate precursors at 180 °C for 6 h, followed by calcination at 500 °C. XRD analysis confirmed successful formation of binary composites comprising anatase TiO 2 and α,β‐PbO, while FTIR revealed interfacial chemical bonding through Pb‐O‐Ti lattice vibrations. The 25:75 PbO‐TiO 2 composite demonstrated superior photocatalytic performance with 70.0% Congo red degradation in the first hour versus 56.8% for pure TiO 2 , representing a 1.23‐fold enhancement (2.80 versus 2.27 mg g − 1 ), primarily governed by heterojunction‐induced charge separation and bandgap narrowing that suppress electron–hole recombination and enhance reactive oxygen species generation. Antimicrobial evaluation against gram‐positive ( S. aureus , L. monocytogenes ) and gram‐negative ( E. coli , S. abony ) bacteria plus C. albicans revealed composition‐dependent enhancement, with 50:50 composite achieving inhibition zones of 10.9 ± 0.29 mm against E. coli and S. aureus . The enhanced antimicrobial efficacy operates through synergistic mechanisms combining photocatalytic reactive oxygen species generation with direct Pb 2 + ion toxicity targeting membrane integrity, enzymatic functions, and DNA structure. These findings establish PbO‐TiO 2 composites as multifunctional platforms addressing conventional TiO 2 limitations while offering enhanced antimicrobial properties for environmental and biomedical applications.