經過短時間迴流加熱後，硫醇包覆的金奈米顆粒可從尺寸大小不一的系統變成為幾乎單一尺寸分布的顆粒系統。我們將探討不同的迴流加熱溫度會如何影響金奈米顆粒的粒徑分布隨時間演化之過程。在相同十二硫醇添加量的條件下，利用不同的溫度對金膠體溶液進行迴流加熱的動作。我們發現當迴流加熱溫度越低，金奈米顆粒達到單一尺寸分散所需的時間越長，並且會得到較大的穩定顆粒尺寸，另外，在更長時間加熱後，奈米顆粒將傾向聚集和粗大化。隨後，我們也改變不同的十二硫醇添加量，試圖去觀察已知的溫度效應是否會受到影響。結果顯示，十二硫醇添加量的不足將造成不同的溫度效應；另外，迴流加熱之後，硫醇效應也被改變了。十二硫醇添加量越多時，迴流加熱後所得的穩定粒徑會增加，此與迴流加熱前的結果是相反的。
除此之外，我們在迴流加熱的過程中額外地加入電場。結果發現，即使在電場作用下，溫度效應對金奈米粒子演化所造成的影響趨勢維持相同。

After a short time reflux heating, thiol-capped gold nanoparticles became nearly monodisperse from a polydispersed particle system. We investigated the reflux-heated temperature how to affect size evolution of gold nanoparticles. With the same amount of dodecanethiol, the gold colloid was reflux heated at different temperatures. We found that reflux-heated temperature decreased, the time that gold nanoparticles achieved monodisperse increased and size of stable gold nanoparticles increased. In addition, after prolonged heating, they have the tendency to aggregate and coalescence. Then, we changed the amounts of dodecanethiol to observe whether the known effects of temperature may be affected. The results showed that the effect of reflux-heated temperature changed while amounts of dodecanethiol were not enough in the gold colloid. In the other hand, the effect of dodecanethiol was changed by reflux heating. Through reflux heating, more amounts of dodecanethiol cause the stable particle size of gold nanoparticle increase, opposite to the results before reflux heated.
Besides, we applied electric field through gold colloid during reflux heating. The results was the effect which the reflux heated temperature under applied electric field have on that gold nanoparticles approached nearly monodisperse system was consistent with that without electric field.

[1] J. Fink, C.J. Kiely, D. Bethell and D.J. Schiffrin, “Self-Organization of Nanosized Gold Particles”, Chem. Mater., 10, 922-926 (1998).
[2] X.M. Lin and C.M. Sorensen, “Ligand-Induced Gold Nanocrystal Superlattice Formation in Colloidal Solution”, Chem. Mater., 11, 198-202 (1999).
[3] X.M. Lin, C.M. Sorensen and K.J. Klabunde, “Digestive Ripening, Nanophase Segregation and Superlattice Formation in Gold Nanocrystal Colloids”, Journal of Nanoparticle Research, 2, 157-164 (2000).
[4] B.A. Korgel, S. Fullam, S. Connolly and D. Fitzmaurice, “Assembly and Self-Organization of Silver Nanocrystal Superlattices: Ordered “Soft
Spheres””, J. Phys. Chem. B, 102, 8379-8388 (1998).
[5] A. Henglein and M. Giersig, “Formation of Colloidal Silver Nanoparticles:  Capping Action of Citrate”, J. Phys. Chem. B, 103, 9533–9539 (1999).
[6] Z.S. Pillai and P.V. Kamat, “What Factors Control the Size and Shape of Silver Nanoparticles in the Citrate Ion Reduction Method?”, J. Phys. Chem. B, 108, 945-951 (2004).
[7] C. Petit, A. Taleb and M.P. Pileni, Self-Organization of Magnetic Nanosized Cobalt Particles, Advanced Materials, 10, 259–261 (1998).
[8] J.S. Yin and Z.L. Wang, “Preparation of Self-assembled Cobalt Nanocrystal Arrays, NanoStructured Materials”, 11, 845–852 (1999).
[9] K.S. Chou and K.C. Huang, “Studies on the chemical synthesis of nanosized nickel powder and its stability”, Journal of Nanoparticle Research, 3, 127–132 (2001).
[10] Y. Houa, H. Kondohb, T. Ohtab and S. Gao, “Size-controlled synthesis of nickel nanoparticles,” Applied Surface Science, 241, 218–222 (2005).
[11] M. Cortie, “Gold Nanoparticles for Physics, Chemistry and Biology”, Imperial College Press, chapt. 13, 355-377 (2012).
[12] D. Seo and H. Song, “Gold Nanoparticles for Physics, Chemistry and Biology”, Imperial College Press, chapt. 5, 103-138 (2012).
[13] P.W. Voorhees, “The Theory of Ostwald Ripening”, Journal of Statistical Physics, 38, 231-252 (1985).
[14] D.K. Lee, S.I. Park, J.K. Lee and N.M. Hwang, A theoretical model for digestive ripening, 55, 5281–5288 (2007).
[15] A.B. Smetana , K.J. Klabunde, C.M. Sorensen, A.A. Ponce and B. Mwale, “Low-Temperature Metallic Alloying of Copper and Silver Nanoparticles with Gold Nanoparticles through Digestive Ripening”, J. Phys. Chem. B, 110, 2155–2158 (2006).
[16] P. Sahu and B.L.V. Prasad, “Effect of digestive ripening agent on nanoparticle size in the digestive ripening process”, Chemical Physics Letters, 525–526, 101–104 (2012).
[17] M.L. Lin, F. Yang, S. Lee, “Digestive ripening for self-assembly of thiol-capped goldnanoparticles: the effects of adding dodecanethiol and reflux-heating”, Colloids and Surfaces A: Physicochem, 448, 16–22 (2014).
[18] L. Supriya and O.C. Richard, “Colloidal Au/Linker Molecule Multilayer Films:  Low-Temperature Thermal Coalescence and Resistance Changes”, Chem. Mater., 17, 4325–4334 (2005).
[19] Y.Q. Wang, W.S. Liang and C.Y. Geng, “Coalescence Behavior of Gold Nanoparticles”, Nanoscale Research Letters, 4, 684-688 (2009).
[20] S.Y. Moon, S.I. Tanaka and T. Sekino, “Crystal Growth of Thiol-Stabilized Gold Nanoparticles by Heat-Induced Coalescence”, Nanoscale Research Letters, 5, 813–817 (2010).
[21] D.V. Leff, P.C. Ohara, J.R. Heath and W.M. Gelbart, “Thermodynamic Control of Gold Nanocrystal Size: Experiment and Theory”, the Journal of Physical Chemistry, 99, 7036-7041 (1995).
[22] M.L. Lin, F. Yang, J. S. Peng, and S. Lee, “Field effect on digestive ripening of thiol-capped gold nanoparticles”, Journal of Applied Physics, 115, 054312 (2014).
[23] J.P. Wilcoxon, R.L. Williamson and R. Baughman, “Optical Properties of Gold Colloids Formed in Inverse Micelles”, The Journal of Chemical Physics , 98, 9933-9950 (1993).
[24] M. Chidambaram, S.U. Sonavane, J. de la Zerda and Y. Sasson, “Didecyldimethylammonium bromide (DDAB): a universal, robust, and highly potent phase-transfer catalyst for diverse organic transformations”, Elsevier, 63, 7696–7701 (2007).