Preparation and properties of T1–T2 multi-modality magnetic submicron particles with the spatial-gap template of cellulose nanocrystal dispersion

T 1 –T 2 multi-modality submicron particles were widely used in clinic imaging, biochemical analysis and biosensor. Here, we prepared a new magnetic submicron particle through the spatial-gap of cellulose nanocrystal (CNC) dispersion as a template.The obtained submicron particles were ellipsoid and had a better magnetic response and relaxation effects. By varying the Fe(acac) 3 to Gd(acac) 3 ratio, it was possible to tune the surface morphology, crystal structure and T 1 –T 2 relaxation effect. More importantly, the pre-drying and burning process had influence on the polycrystalline growth process of Fe(acac) 3 and Gd(acac) 3 mixture, and the slow removal process for the CNC template could endow the compounds with different relaxation effects. By using the spatial-gap of the cellulose nanocrystal dispersion as a template makes it possible to fabricate T 1 –T 2 multi-modality crystalline submicron particles directly and is promising for preparing other CNC-templating based functional materials.