Nanostructure and luminescent properties of sol-gel derived europium-doped Ba2Ca(BO3)2 S.-S. Yao, Y.-Y. Li, L.-H. Xue and Y.-W. Yan Eur. Phys. J. Appl. Phys., 51 3 (2010) 30603 Published online: 02 August 2010 DOI: 10.1051/epjap/2010116