FO5-16/PII.069 Synthesis of silver nanoparticles using plant extracts and microwave assisted chemistry and their potential application for hydrogen production

Resumo

In this contribution, we report on a simple and rapid synthesis of silver nanoparticles (AgNPs) using microwave (MW) assisted chemistry, with different natural extracts. The extracts obtained from plants were used to reduce/stabilize AgNPs and AgNO₃ acted as metal precursor in aqueous medium. The samples were characterized by UV-Vis spectroscopy, revealing the presence of a plasmonic band associated with AgNPs around 410-460 nm. Furthermore, the stability over time for AgNPs prepared using white cabbage was monitored, showing that AgNPs remained stable for at least 21 days. AgNPs were impregnated into titanium dioxide nanoparticles (TiO₂@AgNPs) also prepared by MW irradiation. The photocatalytic activity of TiO₂@AgNPs was tested for H₂ evolution in the photo-reform of methanol under UV-Vis irradiation, demonstrating greater efficiency compared with the TiO₂NPs counterparts.