Influence of agricultural residues on the formation of TiO₂ phases: Real-time in situ X-ray diffraction monitoring in a reaction chamber

This study investigates the influence of agricultural residues on the structural evolution of titanium dioxide (TiO₂) synthesized through a green route using rice husk (C1), sugarcane bagasse (C2), and coconut husk (C3) ashes. Real-time in situ X-ray diffraction (XRD) was employed to monitor phase t...

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Detalles Bibliográficos
Autores: Feitosa, Rodrigo P., Ahmed, Abdullah A. A., Peña García, Ramón, Fonseca, Maria Gardênnia, da Silva Filho, Edson C., Medina Carrasco, Santiago, Orta Cuevas, María del Mar, Osajima, Josy A.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2026
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:dnet:idus________::b150e6f5b421ed0daaec3e9f82f0fd8e
Acceso en línea:https://hdl.handle.net/11441/185442
https://doi.org/10.1016/j.cej.2026.175556
Access Level:acceso abierto
Palabra clave:Agro-residues
Anatase
Rutile
Titanium dioxide
Environmental engineering
Green engineering
Descripción
Sumario:This study investigates the influence of agricultural residues on the structural evolution of titanium dioxide (TiO₂) synthesized through a green route using rice husk (C1), sugarcane bagasse (C2), and coconut husk (C3) ashes. Real-time in situ X-ray diffraction (XRD) was employed to monitor phase transitions during controlled heating up to 900 °C, enabling quantitative tracking of anatase–rutile transformation and crystallite growth by Rietveld refinement. At 800 °C, pure TiO₂ was predominantly rutile (≈94.3%) with only ≈5.7% anatase, whereas C1–TiO₂ and C2–TiO₂ retained ∼50% anatase (49.7% and 51.0%, respectively), and C3–TiO₂ remained anatase-rich (70.1%) due to concurrent formation of priderite (27.8%) and ramsdellite (1.6%). The incorporation of siliceous ashes (C1 and C2) delayed rutile nucleation and reduced crystallite coarsening, indicating that SiO₂ and mineral components hinder atomic diffusion and stabilize anatase at higher temperatures. In contrast, coconut ash (C3) promoted the formation of secondary titanate phases (priderite and ramsdellite), leading to distinct multiphase kinetics. These results demonstrate that the chemical nature of agro-industrial ashes can be used to modulate TiO₂ microstructure and phase stability. The findings provide a quantitative framework for engineering sustainable TiO₂ materials, where the choice of agricultural residue enables control over anatase retention or rutile formation, with direct implications for photocatalytic and surface-active applications.