Green Synthesis of AgNPs from Argentometric Waste using Sandoricum koetjape Pericarp Extract: Structural Characterization and Photocatalytic Activity

The growing need for sustainable nanomaterial production has driven research into more environmentally friendly synthesis methods. This study presents an innovative approach for the green synthesis of silver nanoparticles (AgNPs) by valorizing argentometric laboratory waste using Sandoricum koetjape (kecapi) fruit pericarp extract as a natural reducing agent. Unlike previous studies that separately investigated the chemical reduction of silver waste or plant-mediated reduction of AgNO₃, this work integrates both approaches. Initially, the synthesis of AgNPs from silver waste was optimized using response surface methodology with central composite design (RSM-CCD) to determine optimal reaction conditions. Then, a comparison was conducted on the resulting AgNP characteristics and performance with one synthesized from AgNO₃ under the same conditions. The optimized waste-derived AgNPs exhibited a crystallite size of 12 nm and an average particle size of 38.41 nm, along with a distinct surface plasmon resonance (SPR) peak at 420 nm, confirming their nanoscale formation. Comprehensive characterization by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), XRD, TEM, and zeta potential analysis verified the nanoparticles' functionalization, stability, and crystallinity. In photocatalytic performance tests, the waste-derived AgNPs achieved 96% degradation of methylene blue, comparable to the AgNO₃-derived counterpart.