Response to Queeney and friend's "Comment on 'Methanol on O/Mo( 110): specific site for methyl radical formation'"

Clearly there are differences in the observed reactivities of the "heavily oxidized" surfaces of Mo(1 I0) prepared by Queeney et al. [1] and those prepared by us [2]. We note, however, that our study is in agreement with, and provides fresh insight into, the chemistry of high surface-area (HSA), "real-world" molybdate catalysts. The 3D oxide prepared by us (i) does not produce methyl radicals, the absence of which has been confirmed by Lunsford and co-workers [3] on an HSA molybdate catalyst; (ii) shows a pathway for the production of formaldehyde which matches HSA molybdate catalytic behavior [4]; and (iii) confirms that the appearance of the M o = O species marks the changes in chemical activity of the surface, in agreement with M o O 3 single-crystal studies which show this surface to be unreactive towards methanol [4]. These facts demonstrate that the twodimensional (2D) oxide prepared by both groups is distinctive from the bulk oxide (i.e. HSA molybdate catalysts) in that the 2D oxide produces methyl radicals at elevated temperatures following methanol adsorption, whereas for methanol adsorption on an HSA molybdate catalyst, n o