The present invention is directed to the synthesis of novel delaminated layered zeolite precursor materials prepared by fluoride/chloride anion-promoted exfoliation. The method comprises, for example, using a combination of fluoride and chloride anions at a mild pH in aqueous solution to affect delamination of a layered zeolite precursor. The method can also comprise using a combination of fluoride and chloride anions in a non-aqueous solution comprising an organic solvent. The method may be used in conjunction with either acidification or sonication, or both. The resulting delaminated zeolite precursors are then isolated. Precursors that are then isolated lack amorphous silica content. The UCB-1 product is an example of such a novel oxide material and is obtained in yields in excess of 90% without the need for sonication.