A filter for
trapping and combusting
diesel exhaust particulates and method of making the same. The filter comprises a monolithic substrate coated with a
refractory oxide material which at a frequency of 2.45 GHz heats up said filter from
room temperature to about 600° C. in 5 minutes or less, and wherein said
refractory oxide material has a loss tangent which decreases with increasing temperature such that an equilibrium in said filter temperature is reached at no greater than 1100° C. The
microwave-absorbing material having a composition selected from the group consisting of A1-xMxB1-yM'yO3-alpha, where A and M are selected from the group consisting of Na, K, Rb, Ag, Ca, Sr, Ba, Pb, La, Pr, Nd, Bi, Ce, Th and combinations thereof; where B and M' are selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Rh, Ru, Pt, Zn, Nb, Ta, Mo, W and combinations thereof; wherein, the
chemical formula is electrostatically balanced; (A'aRrM''m)(Z)4(X)6O24, where A' is from Group IA metals; where R is selected from Group IIA metals; where M'' is selected from the group consisting of Mn, Co, Cu, Zn, Y, lanthanides and combinations thereof; where Z is selected from the group consisting of Zr, Hf, Ti, Nb, Ta, Y, lanthanides, Sn, Fe, Co, Al, Mn, Zn, Ni, and combinations thereof; where X is selected from the group consisting of P, Si, As, Ge, B, Al, and combinations thereof.