Mesoporous aluminophosphate materials with variable amounts of zirconium have been synthesized at room temperature using a nonionic surfactant tri-block copolymer (PEO20PPO7PEO20) as the structure-directing agent. Powder X-ray diffraction of as-synthesized and calcined AIPO and ZrAIPO mesoporous materials shows a single broad peak near 2 theta = 2.5 degrees, indicative of the average pore-pore correlation distance. Electron probe microanalysis shows that the ratio of P/Al in the powders is similar to 0.5, far lower than 1.0 for an ideal aluminophosphate framework. XRD, TEM, and N-2 adsorption data indicate that the calcined samples consist of wormlike tubular materials having surface areas > 350 m(2)/g and pores in the mesopore range. Electron spin resonance (ESR) studies of the gamma-irradiated and evacuated ZrAIPO samples show signals due to Zr3+ that increase with Zr content in addition to signals due to framework defects (i.e., V centers) and H atoms. The line shape and g values observed for Zr3+ are best explained as arising from a trivalent zirconium ion situated at the framework tetrahedral sites.