Calcium Aluminate (CaAl₂O₄) synthesis routes: a systematic literature review

Abstract

This article presents a systematic review of the synthesis routes applied to calcium aluminate (CaAl₂O₄) between 2015 and 2025, aiming to identify, organize, and critically analyze the methods employed. The selection of studies followed strict eligibility criteria, including language, open access, peer review, and explicit focus on material synthesis. Fourteen articles were included, describing methods such as solid-state reaction, solution combustion, sol-gel routes (traditional, Pechini, citrate-nitrate), molten salt-assisted sintering, direct foaming, and hybrid strategies. The results highlight a predominance of techniques that combine morphological control, reduced synthesis temperatures, and energy efficiency. Wet chemical routes, particularly sol-gel variations, stand out for enabling the production of nanocrystalline powders with luminescent properties. Furthermore, a growing trend is observed in the chemical modification of calcium aluminate cements through acid-base reactions with polyphosphates, expanding the material's application scope. This review contributes to the consolidation of knowledge in the field by compiling previously scattered information, offering valuable insights for the planning of more effective, sustainable, and application-oriented synthetic approaches.