New thin-film dielectrics and nanolaminates have been synthesized via aqueous-solution deposition of Hf and Zr sulfates, where facile gelation and vitrification of the precursor solution have been achieved without organic additives. X-ray reflectivity, imaging, and metal-insulator-metal capacitor performance reveal that smooth, atomically dense films are readily produced by spin coating and modest thermal treatment (T < 325 °C). Dielectric characteristics include permittivities covering the range of 9–12 with breakdown fields up to 6 MV cm-¹. Performance as gate dielectrics is demonstrated in field-effect transistors exhibiting small gate-leakage currents and qualitatively ideal device performance. The low-temperature processing, uniformity, and pore-free nature of the films have also allowed construction of unique, high-resolution nanolaminates exhibiting individual layers as thin as 3 nm.