Enhanced room temperature ferromagnetism in hydrogenated Zn0.98Mn0.02O

After annealing in H2 atmosphere at 500 °C for 2 h, enhanced room temperature ferromagnetism has been observed in the paramagnetic Zn0.98Mn0.02O powders synthesized by sol–gel method. Mn ions in interstitial sites have been clearly resolved by Raman measurement in the as-prepared Zn0.98Mn0.02O powders and those annealed in Ar and air, while hydrogenation facilitates the interstitial Mn ions to substitute the Zn sites. The structural characterizations have confirmed the incorporation of the interstitial H and excluded the ferromagnetic contribution of O vacancies. Our results clearly demonstrate the ferromagnetic mediation between the neighboring substituted Mn2+ ions by the interstitial H ions.