Journal Article

High-temperature ferromagnetism of Cu-doped PbPdO2 nanograin films

Wu, Y. C., Huang, J. C. A., Ye, D. C., Qiu, E. B., Su, H. L., Mei, C., Zhang, Z.

2017

Overview

The single-phase, body-centered orthorhombic-structured, Cu-doped PbPdO 2 films with a nanograin structure were synthesized by using the sol–gel spin-coating method and an oxidation treatment. It was found that large amounts of Pb vacancies exist in the nanograin film and Pb ions possess a mixed valence state of 2+ and 4+. Besides the superparamagnetism and the charge ordering state, the magnetic studies displayed that ferromagnetism, which can persist up to 380 K, exists in the Cu-doped PbPdO 2 nanograin film. As a peculiar characteristic of the spin gapless semiconductor, the ferromagnetic saturation magnetization increasing unusually with temperatures above 300 K was also discovered. The bound magnetic polarons based on the Pb vacancies, the doped Cu 2+ ions, and the Pb ions with a valence higher than 2+ were believed to be the origin of such high-temperature ferromagnetism. Graphical abstract

• Publisher: Springer US,Springer Nature B.V
• Subject: Ceramics / Chemistry and Materials Science / Composites / Copper / electronic / Ferromagnetic materials / Glass / High temperature / Inorganic Chemistry / magnetic and ferroelectric applications / Magnetic saturation / Materials Science / Nanotechnology / Natural Materials / Optical and Electronic Materials / Original Paper: Sol-gel and hybrid materials for dielectric / Oxidation / Sol-gel processes / Spin coating / Vacancies / Valence