The size effect study in GdMn2O5 nanorods

• Main Authors: Cheng-Yu Weng, 翁誠佑
• Other Authors: Chun-Chuen Yang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/92551884253691499875

碩士 === 中原大學 === 物理研究所 === 99 === In this study, hydrothermal method was employed to synthesis the GdMn2O5 nanorods. Different rod sizes were growth by annealing procedure in different temperatures. X-ray, FE-TEM and PPMS were used to characteristic the crystal structure, appearance, size and magnetic susceptibility of these obtained samples. The four sizes and appearance of GdMn2O5 nanorods are identified by FE-TEM images and labeled in length × width as 52(17) nm×27(7) nm, 67(18) nm×34(8) nm, 80(28) nm×35(11) nm and 206(77) nm×107(40) nm. A magnetic susceptibility peak appeared at around 40 K in both 80(28) nm×35(11) nm and 206(77) nm×107(40) nm samples. SAED experiments also revealed the long axis is corresponding to the a-axis of the crystal. We found the effect magnetic moment are correlated with the length of long axis and Mn3+ Pyr -O(3)-Mn4+ Oct bound length. This implies the size effect is controlled the magnetic behavior of GdMn2O5 nanorod system. And critical size of GdMn2O5 nanorods is in between 80 and 67 nm along a axis.