Porous silicon nanostructures: Synthesis, characterization, and their antifungal activity

The use of synthetic pesticides has come under scrutiny, and there has been a subsequent shift toward the investigation of alternative methods for the treatment of plant diseases. One notable advancement in this field is the utilization of porous silicon (PS) powder as a sustainable antifungal agent. The synthesis of PS nanoparticle (PS-NP) powder was carried out using the environmentally friendly ultrasonication process. X-ray powder diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, UV-VIS absorbance, and photoluminescence were some of the methods used to characterize PS-NPs. The different characterization methods revealed the formation of a nanocrystalline structure possessing a cubic Si crystalline quality. The crystal size of PS-NPs, as determined from X-ray diffractometer data, ranges from 36.67 to 52.33 nm. The obtained PS has a high band gap of 3.85 eV and presents a photoluminescence peak at 703 nm. The antifungal activity of the synthesized PS-NPs was assessed against three molecularly characterized fungi, namely Rhizoctonia solani, Fusarium oxysporum, and Botrytis cinerea, which were obtained from tomato plants. The concentration of PS-NPs at 75 µg/mL exhibited the highest enhancement in growth inhibition percentages as compared to the control group. R. solani had the highest inhibition percentage of 82.96%. In conclusion, the encouraging structural properties and antimicrobial capabilities of PS-NPs pave the way for their application across diverse technological industries. To the best of our knowledge, this is the first in vitro study of PS-NPs to evaluate their fungal control efficiency.