Vacancy defect activation spin magnetic effect of Ni(OH)2 enhanced oxygen catalysis.

The oxygen evolution reaction (OER) process involves the magnetic reversal of oxygen-containing intermediates, and the influence of defect structures on the magnetic behavior of catalysts might play a crucial role in this process. There is scarce research on the intrinsic relationship among defects, magnetism and catalysis. Herein, cation vacancy β -Ni(OH) 2 nanosheets were successfully prepared through alkaline selective etching. To further analyze their spin-magnetic behavior, we found that the presence of defects caused the transformation of Ni(OH) 2 from antiferromagnetic to ferromagnetic. Furthermore, to further elucidate their intrinsic spin-magnetic effects, it was observed that the initially antiferromagnetic β -Ni(OH) 2 exhibited almost no spin-magnetic response upon the introduction of a magnetic field, with the overpotential almost unchanged. Conversely, introducing defect structures showed a noticeable spin-magnetic effect, reducing the overpotential by 20 mV at 20 mA cm−2. The combination of defects and magnetic fields provides new principles for developing high-performance catalysts and understanding catalytic mechanisms at the spin-electronic level. • Ni 1-x Vac x (OH) 2 was prepared to investigate the spin-magnetic behavior of defect. • The defects of Ni(OH) 2 led to transformation from antiferromagnetic to ferromagnetic. • The spin-magnetic effect can reduce the overpotential by 20 mV at 20 mA cm−2. [ABSTRACT FROM AUTHOR]