1. Porous and biphasic materials through solid state reactions
Daniel P. Shoemaker, Eric S. Toberer, and Ram Seshadri
Materials Department and Materials Research Laboratory,
University of California, Santa Barbara CA 93106, USA
We are continuing our investigation of rapid, spontaneous routes to the self-assembly of mesoporous and biphasic materials. By utilizing novel chemical techniques and considering complex phase equilibria, we are establishing a toolkit for the production of composites with potential applications ranging from filtration and catalysis to magnetoelectric coupling and magnetic exchange bias.
Coercivity
Loop shift
Ni/MnO nanocomposites are produced by hydrogen reduction of NixMn3-xO4. Because the Ni nanoparticles are mostly embedded within the MnO matrix, strong interfacial magnetic coupling leads to exchange bias. This exchange bias is characterized by broadening and shifting of the hysteresis loop along the field axis upon cooling below the Néel temperature of MnO (TN = 119 K).
Interior (FIB)
Exterior (SEM)