We report single yttrium sites anchored on carbon-coated TiO<INF>2</INF>for efficient and stable electrocatalytic N<INF>2</INF>fixation, delivering an NH<INF>3</INF>faradaic efficiency exceeding 11.0% and an NH<INF>3</INF>yield rate as high as 6.3 mu g<INF>NH<INF>3</INF></INF>h<SUP>-1</SUP>mg<INF>cat.</INF><SUP>-1</SUP>at low overpotentials, thus surpassing many reported metal electrocatalysts.