Preparation of MgO nano-rods with strong catalytic activity via hydrated basic magnesium carbonates

MgO nano-rods of several microns in length and 50–100 nm in width were prepared by calcining nesquehonite phase, obtained by simple precipitation using (NH4)2CO3 under ambient condition. The MgO nano-rod with reasonably high surface area (75–120 m2 g−1) exhibits strong activity in solvent-free base catalyzed Claisen-Schmidt condensation giving 99% conversion in 2 h and is easily recyclable with no significant change in catalytic activity. Presence of numerous basic sites of different strengths (surface hydroxyl groups, low coordinate O2− sites) is attributed to the observed effect.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Simple solution route for preparing nesquehonite rods. ► Nano-building block based MgO rods as base catalyst. ► Calcination of nesquehonite in nitrogen gives highly active MgO catalyst. ► Large surface area and active site density is attributed to the strong activity.