Unusual double ligand holes as catalytic active sites in LiNiO.

Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance for energy conversion devices. The anionic redox allows formation of O-O bonds and offers higher OER activity than the conventional metal sites. Here, we successfully prepare LiNiO with a dominant 3dL configuration (L is a hole at O 2p) under high oxygen pressure, and achieve a double ligand holes 3dL under OER since one electron removal occurs at O 2p orbitals for Ni oxides.

Giant Exchange-Bias-Like Effect at Low Cooling Fields Induced by Pinned Magnetic Domains in Y NiIrO Double Perovskite.

Exchange bias (EB) is highly desirable for widespread technologies. Generally, conventional exchange-bias heterojunctions require excessively large cooling fields for sufficient bias fields, which are generated by pinned spins at the interface of ferromagnetic and antiferromagnetic layers. It is crucial for applicability to obtain considerable exchange-bias fields with minimum cooling fields.

Comparative Study on the Magnetic and Transport Properties of B-Site Ordered and Disordered CaCuFeOsO.

The B-site Fe/Os ordered and disordered quadruple perovskite oxides CaCuFeOsO were synthesized under different high-pressure and high-temperature conditions. The B-site ordered CaCuFeOsO is a system with a very high ferrimagnetic ordering temperature of 580 K having the Cu(↑)Fe(↑)Os(↓) charge and spin arrangement. In comparison, the highly disordered CaCuFeOsO has a reduced magnetic transition temperature of about 350 K.

Realization of a Half Metal with a Record-High Curie Temperature in Perovskite Oxides.

Half metals, in which one spin channel is conducting while the other is insulating with an energy gap, are theoretically considered to comprise 100% spin-polarized conducting electrons, and thus have promising applications in high-efficiency magnetic sensors, computer memory, magnetic recording, and so on. However, for practical applications, a high Curie temperature combined with a wide spin energy gap and large magnetization is required. Realizing such a high-performance combination is a key challenge.