Synthesis of [Fe(hptrz)3](OTs)2 spin crossover nanoparticles in microemulsion

Synthesis of the [Fe(hptrz)3](OTs)2 spin crossover nanoparticle samples was performed. Transmission electronic microscopy was used to determine the size and size distribution of the nanoparticle samples for which a size range of 35–70 nm was found – depending on the composition and the stoichiometry of the reverse micelle hexane-tergitol-water system. The factors susceptible to influence the aggregation degree of the nanoparticles, i.e., the starting experimental conditions, the experiment time and the effect of sonication were also studied. In comparison with the bulk powder sample, these nano-materials still exhibit spin crossover near room temperature with a hysteresis loop. The size-properties relationship concerning the present compound and analogue complexes within this family is also discussed.

Graphical abstractSyntheses of spin crossover nanoparticles of the 1D coordination polymer [Fe(hptrz)3](OTs)2 was performed by application of the reverse micelle technique. In comparison with the bulk sample, the size reduction effect appears to be rather weak on the spin transition behavior since cooperative first-order thermal spin transition with hysteresis loop is maintained in nanometric objects of ca. 35–70 nm.Figure optionsDownload full-size imageDownload as PowerPoint slide