Abstract: Pb₃(PO₄)₂ and BiPO₄ were prepared by the precipitation method.The surface composition, structure, chemisorption properties and the behavior of laser stimulated isobutane selective oxidation were investigated by means of the techniques of XRD, IR, TPDand LSSR.The results showed that both Lewis base sites, O^2- on the surface P＝O　or Pb(Bi)—O bonds, and Lewis acid site, Pb²⁺ or Bi³⁺ appear on the surface of Pb₃(PO₄)₂ or BiPO₄. Two methyl hydrogens in isobutane molecule can be chemisorbed at the terminal oxygen of neighboring Lewis base sites P＝O bonds on the surface of phosphate.Under the conditions of 0.1 MPa and 200 with the 1056 cm^-1 laser photons exciting the P＝O bonds for 1000 times, the oxidative dehydrogenation reaction of isobutane occurred remarkably with the product selectivity of isobutene over 95%.In the course of LSSR, the conversion of isobutane depends on the vibrational structure of the solid materials and the adsorbing amount of is obutane on the excited P ＝O bonds, the selectivity of the reaction product depends on the adsorbing state of isobutane on the solid surface.

Key words: Laser stimulated surface reaction, Phosphate, Oxidative dehydrogenation, Isobutane, Isobutene