DC-magnetization measurements on electrochemically delithiated

✍ Scribed by Kazuhiko Mukai; Jun Sugiyama

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 407 KB
• Volume: 150
• Category: Article
• ISSN: 0038-1098
• DOI: 10.1016/j.ssc.2010.03.003

✦ Synopsis

The magnetism of electrochemically delithiated Li x [Ni 1/2 Mn 3/2 ]O 4 samples with space group P4 3 32 has been studied by dc-magnetization measurements. For the x = 1 sample, the temperature (T ) dependence of the magnetization/field (=M/H) showed the appearance of a spontaneous magnetization below 130 K.

Moreover, since a clear ferromagnetic (FM) M-H loop was observed at 5 K and its saturated magnetization (M s ) was almost equivalent to the predicted value (= 3.5µ B ), the whole sample was found to enter into a FM phase below 130 K (=T C ). A very similar FM behavior was also obtained for the x = 0.5 sample below 130 K, while the magnitude of M s was almost a half of that for the x = 1 sample. In contrast to the x = 1 and 0.5 samples, M for the x = 0.05 sample increases almost linearly in the H range between ∼5 and 55 kOe. Therefore, it is found that the fully delithiated Li x [Ni 1/2 Mn 3/2 ]O 4 sample is in a paramagnetic or antiferromagnetic state even at 5 K.