Structure–Morphology–Defect Relationships in CaTiO₃-Based Perovskites for Environmental Applications

Résumé

This review provides a comprehensive and critical analysis of the structure–morphology–defect relationships in CaTiO₃-based perovskites, with an emphasis on their environmental applications, particularly in water treatment and photocatalytic degradation processes. The paper systematically examines the influence of crystal structure, synthesis routes, microstructural evolution, and defect chemistry on the functional performance of CaTiO₃ materials. Special attention is  given to the role of crystallographic phase stability, particle size distribution, surface area, porosity, and aggregation phenomena in controlling adsorption capacity and charge carrier dynamics. Different synthesis strategies—including solid-state reaction, sol–gel processing, hydrothermal and microwave-assisted routes, spray pyrolysis, and green mechanochemical methods—are comparatively evaluated with respect to their effects on morphology control and defect formation. Furthermore, the integration of CaTiO₃ with carbon-based materials and the development of doped or composite systems are analysed as strategies for enhancing photocatalytic activity and environmental stability.
By correlating structural features with the physicochemical performance indicators reported in the literature, this review identifies current limitations, unresolved challenges, and promising directions for future research. The analysis aims to provide a coherent framework for the rational design and optimization of CaTiO₃-based perovskites in environmental remediation technologies.