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The studies on mechanical treatments of layered alkali metal oxides are limited despite their diverse compositions/ structures and potential for property tuning. In this work, we vibratory mill Cs 0.7 Zn 0.35 Ti 1.65 O 4 , K 0.8 Zn 0.4 Ti 1.6 O 4 , and Cs 2 Ti 6 O 13 for up to 4 h, during which the lepidocrocite-type structure and the plate-like morphology are well preserved. X-ray diffraction (XRD) indicates a tiny (≤0.6 Å) interlayer expansion accompanied by the enhancement of the preferred orientation along the stacking direction. Chemical analyses across multiple length scales suggest Cs deintercalation, elemental redistributions, and bulk-to-surface (or crystal edge) Cs migration. This ball-milling-induced Cs-rich moiety partially blocks the surface acid sites, although the solids still show a dominating acidic character. The ball-milled samples Cs 0.7−p Zn 0.35−q Ti 1.65 O 4−δ contain vacancies between the sheets (p) and at the sheets (q and δ). It is deduced from Sanderson's electronegativity equalization principle and experimentally verified by Xray photoelectron spectroscopy (XPS) that ball milling increases (decreases) the partial charge at the surface acidic Ti 4+ /Zn 2+ (basic O 2− ) sites. These nonporous solids (≤20 m 2 •g −1 ) contain water sorbed on the external surface as high as 1.1 mol•mol −1 , which is comparable to that in a water-intercalated sample. Our work expands the current understanding of the reactivity vs robustness in layered alkali titanates under physically demanding conditions, complementing knowledge gathered via the soft chemistry approach.

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The (1 − x)Bi(Zn 1/2 Ti 1/2)O 3-xPbZrO 3 solid solution ceramics were prepared by using solid-state reaction method, and their ferroelectric properties were investigated. It was found that the perovskite structure is stable for compositions with x ≥ 0.900. Within this composition range, the crystal structure of the solid solution preserves the orthorhombic symmetry of PbZrO 3 (PZ). The Curie point of the ceramics was found to decrease with increasing Bi(Zn 1/2 Ti 1/2)O 3 (BZT) content. The intermediate ferroelectric phase of PZ was stabilized by BZT addition and exists within a much wider temperature range in the solid solution.