“…The reaction is catalyzed by metal nanoparticles such as Au [ 10 , 12 ], Ag [ 13 ], or Pt [ 10 , 11 ] at the substrate surface, and the oxidizing agents are H 2 O 2 [ 10 – 13 ], KMnO 4 [ 14 ], or Fe(NO 3 ) 3 [ 15 ]. It has been shown that SiNWs, which were obtained by MACE, are found to possess such remarkable optical properties as visible photoluminescence (PL) [ 16 ], extremely low total reflection [ 17 , 18 ], enhancement of Raman scattering [ 17 , 19 – 21 ], coherent anti-Stokes light scattering [ 22 ], interband PL [ 17 , 19 – 21 ] and efficiency of generation of third harmonics [ 23 ] in comparison with the corresponding intensities for c-Si, and sensitivity of visible PL to molecular surroundings [ 24 ]. However, HF is rather toxic and may also result in hypocalcemia and hypomagnesemia [ 25 ].…”