Novel Ba5Zn4Y8O21:Eu3+ nanocrystals have been synthesized via combustion method. The process yields better purity and saves time as well as energy. Judd-Ofelt intensity parameters have been calculated for these nanocrystals. The crystal structure and nano-scaling has been studied using XRD and TEM. These nanophosphors are suitable candidate for futuristic Single-Phased White LEDs.