A goal of chemists for many years has been to control the structure of solid-state compounds to induce desired chemical properties. A porous metal phosphonate compound with chemically active pillaring groups, which allow for the direct production of hydrogen peroxide from hydrogen and oxygen, has been designed. The porous compound, Zr2(PO4)(O3PCH2CH2-bipyridinium-CH2CH2PO3)X3ċ3H2O (X=halide) was prepared by low-temperature hydrothermal reaction. The organic groups of this material act as pillars for the inorganic layers, leading to large pores (ca. 8×9 Å) in the solid. Platinum and palladium colloids can be incorporated into the structure by ion-exchanging the free halide with a solution of K2MCl4(M=Pd or Pt) followed by hydrogen reduction. In these materials, the Pt and Pd colloids act as microelectrodes for the reduction of viologen by hydrogen, which selectively reduces oxygen to hydrogen peroxide. Treatment of aqueous suspensions of these porous catalysts with H2and O2gases at atmospheric pressure leads to H2O2solutions with concentrations as high as 0.21M. Reactions carried out at higher pressures lead to significantly higher concentrations of H2O2. The yield of H2O2based on H2consumed was estimated at 40%.