Photoluminescence Studies of Li-Doped Si Nanocrystals

We investigate the optical properties of Lidoped Si nanocrystals (both freestanding and matrixembedded), which are potentially an important material for the new generation of lithium‐ion batteries. Our samples contain 10 – 100 Li atoms per one Si nanocrystal and their lattice is slightly expanded. The photoluminescence (PL) spectra of the S‐band of Lidoped Si nanocrystals are blue‐shifted by ~30nm compared to the undoped Si nanocrystals and their PL lifetime is correspondingly shorter. The F‐band emission is almost unaffected by Li doping. The observed changes in the PL performance are probably caused by Si lattice expansion induced by Li insertion. The reported spectral blue shift is favourable for certain photonic applications.