Promoters and precursors can control oxide phase, dispersion, and per-site reactivity of supported oxide catalysts. Previously, dispersed FeOx-SiO2 resulted from Fe3+ ethylenediaminetetraacetate (FeEDTA(-)) precursors, with NaFeEDTA giving enhanced dispersion and oxidation rates vs. NH(4)FeEDTA. Here, catalysts were synthesized by sequential alkali deposition and Fe3+ impregnation. At up to 0.9 Fe nm(-2) from NH(4)FeEDTA and equimolar alkali, UV-visible and H-2 TPR were consistent with isolated Fe3+ and small FeOx clusters. Omitting alkali, using Fe(NO3)(3), or using Fe/alkali > 1 gave evidence of larger agglomerates. For Fe/alkali <= 1 on non-porous SiO2, initial turnover frequencies in adamantane oxidation using H2O2 were independent of surface density. TOF increased as 6.3, 8.8, 15.4, and 20.9 (+/- 0.3) ks(-1) for Li+, Na+, K+, and Cs+, respectively, increasingly linearly with decreasing electronegativity. These results give a synthesis-structure-function taxonomy with alkali as an electronic and structural promoter of dispersed FeOx species for alkane selective oxidation. (C) 2012 Elsevier Inc. All rights reserved.