In The last years, nanostructures of materials, as the porous silicon nanowires (PSiNWs), have been used extensively studiedfor the development of several chemical, electro-chemical and biologic sensors, because of their physical and chemicalcharacteristics. The PSiNWs present a unique property, like the biocompatibility and the multifunctional. The PSiNWscan be elaborated from lightly n-type (100) silicon substrate by Ag assisted chemical etching method. After porous siliconnanowires growth a multitude of charatcterisation by different techniques has been carried out as, scanning electron microscopy(SEM), spectrophotometry (reflexion-transmission), photoluminescence (PL), infrared spectroscopy and secondary ion massspectrometry (SIMS).As interesting results, a reflectance value lower than 2% and a strong photoluminescence signal, with a pic centered at the600 nm have been found from the elaborated samples. Finally, the obtained results can find application in low-cost and highefficiency porous silicon nanowires based solar cells.