Photoredox catalysis driven by visible light provides an efficient and environmentally friendly strategy for organic synthesis. In this study, we report a novel heterogeneous photocatalyst developed by immobilizing 1,5-diaminoanthraquinone (DAAQ) onto functionalized silica nanoparticles (SNPs). The photocatalyst was thoroughly characterized using various techniques, including TEM, SEM, UV-vis, FT-IR, ss-NMR, DLS, and XPS. Its photocatalytic performance was assessed in three reaction systems: the dehalogenation of aryl halides, cross-dehydrogenative coupling (CDC) of -aryl-1,2,3,4-tetrahydroisoquinolines, and singlet oxygen generation energy transfer. The SNPs-DAAQ catalyst showed high photocatalytic activity and excellent recyclability, achieving up to 10 cycles. Additionally, the nanomaterial exhibited promising antibacterial properties against . The catalyst's robust performance and potential applications in green chemistry and antibacterial devices highlight its value in designing sustainable synthetic methodologies.