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The effect of pre-calcination of titania on the nature of interaction that occurs between titania and a dopant such as metal oxide (molybdenum oxide) was examined using Raman spectroscopy and X-ray diffraction. The presence of diffraction peaks at 2θ ​= ​9.7° and 13.6° for the catalytic materials could be associated with surface molybdate species which will be useful for many catalytic reactions. The presence of these surface molybdate species were also confirmed by Raman spectroscopy by the presence of lines at 932, and 883 ​cm−1 for the catalytic materials in which the support was not previously calcined. However, in addition to the surface molybdate such as MoO, Mo–O–Mo, bulk MoO3 was present in the materials in which the support was calcined before wet impregnation of molybdenum oxide. Therefore, the surface of MoO3/TiO2 can be tuned by simple calcination of the titania before the addition of the molybdenum oxide.