Synthesis of MgO nanocrystals with abundant surface defects via a carbonization method employing CO2 gas as starting material

Taking its unique property into consideration, uniformly dispersed MgO nanoparticles with abundant surface oxygen defects was primarily synthesized via a facile carbnization method employing CO2 gas as carburizer in this study. After reaction at 60 degrees C for 2 h, Mg2+ ions were totally carbonized to caterpillar-like Mg-5(CO3)(4)(OH)(2)(H2O)(4) precursor. And through decarbonization and dehydration processes during calcination, as-prepared Mg-5(CO3)(4)(OH)(2) (H2O)(4) precursor with micro-nano structure was thouroughly converted to well-crystallized MgO nanospheres. As-evidenced by the UV-VIS-NIR diffuse reflectance spectroscopy, due to the largely intensified low-coordinated oxide ions at the corner and kink sites with decreasing the average size, the forbidden band gap of as-prepared MgO nanocrystals is 5.3 eV, which thus endows it intriguing applications in different fields. (C) 2016 Elsevier Ltd. All rights reserved.