Abstract: A catalyst composition for the oxidation and ammoxidation of hydrocarbons comprising a plurality of silica sol particles with different average particle sizes, and a complex of metal catalytic oxides having the formula: AaBbCcBidMOeOx, wherein ??(i) A is one or more of Li, Na, K, Cs, Rb, In, and TI B is one or more of Ni, Mn, Co, Mg, Ca, and Zn C is one or more of Fe, Cr, Ce, Cu, V, W, Sb, Sn, Ge, P, B, Ga, Te, Nb, and Ta, a is 0.0-1.0 b is 0.0-12.0 c is 1.0-12.0 d is 0.0-2.0 e is 12.0-14.0; or AaBbSb12Ox, wherein ??(ii) A is one or more of Fe, Cr, Ce, V, U, Sn, Ti, Ga, and Nb B is one or more of Mo, W, Co, Cu, Te, Bi, Ni, Ca, and Ta a is 0.1-16 b is 0.0-12.0. In both (i) and (ii), the value of x depends on the oxidation state of the metals used. Furthermore, a process for producing said ammoxidation catalyst is disclosed.