Structure and effect of diamagnetism on manganese lithium phosphate glass to cathode materials application
Pichitchai Butnoi, Wipada Senanon, Narong Chanlek, Yingyot Poo‐arporn, Supree Pinitsoontorn, Santi Maensiri, Prayoon Songsiriritthigul, Pongtanawat Khemthong, Pinit Kidkhunthod
Abstract
1-x(Li2O–2P2O5)-xMnO2 glasses where x = 0.2, 0.3 and 0.4 mol%, respectively, were synthesized by melted-quenching method. The Mn and P oxidation states and local structures around Mn and P-ions including Mn–O and P–O bonding distances and coordination numbers have been studied via X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), respectively. XANES results exhibit a coexistence of oxidation state of Mn2+ and Mn3+ with a mean value of 2.82. Moreover, Mn and P K-edge EXAFS show the Mn–O and P–O bonding distances of approximately 2.083–2.094 Å and 1.766–1.774 Å, respectively. A paramagnetism was found for all Mn–P glasses. Additionally, the coercive field (Hc) and remnant magnetization (Mr) increased with increasing Mn contents. However, the low specific capacitances are seriously obtained (<40 F g−1) suggesting the effect of natural diamagnetism of lithium phosphate based-glass unlike the borate based-glasses which originally exhibit paramagnetism.