Optical spectroscopy of Nd3+ ions in a nanostructured glass matrix

► Nd3+-emission enhancement was due to energy transfer from the CdS nanocrystals. ► Nd3+-emission quenching was due to upconversion, multiphonon decay and energy transfer. ► Judd-Ofelt parameters were calculated considering the presence of CdS nanocrystals. ► Changes in the chemical environment of Nd3+ ions around CdS nanocrystals were evidenced.