Growth and characterization of Punica granatum dye- incorporated NLO-active sodium p-nitrophenolate dihydrate (NaPND) single crystals

This study presents a novel approach to modifying sodium p-nitrophenolate dihydrate (NaPND) single crystals by doping them with a natural dye extracted from Punica granatum (PG) fruits. The PG dye was characterized using HPLC and GC–MS to confirm its purity and determine its chemical composition. PG-doped crystals (PG–NaPND) exhibit enhanced optical transmittance (65% to 73%) and thermal stability (135 °C to 146 °C) compared to pure NaPND. Single-crystal XRD confirms structural integrity, while FT–IR and FT–Raman analyses verify dye incorporation. PG–NaPND shows 1.16 times greater SHG efficiency than NaPND and 5.52 times greater than KDP in SHG analysis. The Z-scan method highlights PG–NaPND as a promising material for NLO applications by revealing strong third-order nonlinear and optical limiting properties.