1 Supporting Information Enhancement of quantum yield of LaPO 4 :Ce 3+ :Tb 3+ nanocrystals by carbon nanotube induced suppression of the 1-dimensional growth Jie Fang, a,b Yanglong Guo, a Guanzhong Lu,* a Colin L. Raston b and K. Swaminathan Iyer* b a Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis, East China University of Science and Technology, Shanghai 200237, P. R. China. E-mail: gzhlu@ecust.edu.cn b Centre for Strategic Nano-Fabrication, School of Biomedical, Biomolecular and Chemical Sciences The University of Western Australia, Crawley, WA 6009, Australia. E-mail: swaminatha.iyer@uwa.edu.au Experimental All chemicals utilized in the synthesis were purchased from Sigma-Aldrich without further purification. High purity single wall carbon nanotubes (SWCNTs) was purchased from Chengdu Organic Chemicals Co. Ltd., Chinese Academy of Sciences. The SWCNT was functionalized using a literature method for producing water soluble SWCNTs. Briefly, the SWCNT was functionalized by treating 10 mg in acid mixture of 10ml of concentrated HNO 3 and 10 ml of concentrated H 2 SO 4 followed by heated at 80°C for 2.5 hours. 1 The SWCNTs were purified by multiple washes with water to neutral pH. LaPO 4 :Ce 3+ :Tb 3+ and LaPO 4 :Ce 3+ :Tb 3+ @SWCNT were prepared with the literature method using a previously described rotating tube microfluidic platform to aid room temperature crystallization of well defined nanoparticles. 2 In a typical synthesis of LaPO 4 :Ce 3+ :Tb 3+ , 1 mM LnCl 3 solution (a mixture of 40% LaCl 3 , 45% CeCl 3 and 15% TbCl 3 with a total concentration of 1 mM) and 1mM NaH 2 PO 4 were fed from two feed jets into the rotating tube continuously at a feed rate of 60 ml/min, and rotational speed of the tube was fixed at 1700 rpm. The products were collected at Supplementary Material (ESI) for Dalton Transactions This journal is © the Royal Society of Chemistry 2011