Vanadium phosphate catalyst used industrially for the selective oxidation of n-butane to maleic anhydride was prepared by using dihydrate method. VOPO₄·2H₂O was intercalated with Co-complex (Co(acac)2) and was further refluxed to obtain hemihydrates precursor, VOHPO₄·0.5H₂O. This precursor was further calcined in n-butane/air environment to obtain activated pyrophosphate catalyst, (VO)₂P₂O₇.  The intercalation was confirmed by the presence of a new diffraction peak which occurred at 2θ = 6.8º and 13.5º. Temperature programmed reduction (TPR) in hydrogen of the intercalated catalyst shows a sharp reduction peak with larger amount of active oxygen species being removed (compared to unintercalated catalyst) from V⁴⁺ phase. An improved of n-butane conversion is expected due to the increment of the active oxygen species (O-) which responsible to the activation of n-butane. Higher amount of oxygen linked to V⁵⁺ will also contribute to the enhancement of the n-butane conversion.