Photocatalysis is a promising advanced water treatment technology, and recently the possibility of using hydrogenation to improve the photocatalytic efficiency of titanium dioxide has generated much research interest. Herein we report that the use of high-temperature hydrogenation to prepare black TiO2 primarily results in the formation of bulk defects in the material without affecting its electronic band structure. The hydrogenated TiO2 exhibited significantly worse photocatalytic activity under simulated sunlight compared to the unhydrogenated control, and thus we propose that high-temperature hydrogenation can be counterproductive to improving the photocatalytic activity of TiO2, because of its propensity to form bulk vacancy defects.

Superparamagnetic iron oxide nanoparticles (SPIONs) comprise a fundamental technology class within the emerging field of nanomedicine, and have been extensively researched for cancer imaging and therapy. This review article will discuss the chemistry and design considerations associated with the synthesis of SPIONs and their incorporation into pharmaceutical formulations. Specific synthesis methods discussed include coprecipitation, thermal decomposition, microemulsion and solvothermal synthesis, as well as surface treatments and encapsulations to improve the nanoparticle biocompatibility and efficacy. Emerging applications of novel particle designs as MRI contrast agents are also discussed.

Photocatalysis over titanium dioxide is a promising technology for water purification and degradation of emerging contaminants, however, catalyst efficiency and recovery after the photocatalytic reaction are key challenges that have limited the practical deployment of TiO2 in water treatment applications. Herein we report the synthesis of core-shell, superparamagnetic gamma-Fe2O3@SiO2@TiO2 colloidal nanospheres with a mesoporous TiO2 shell, their characterization, and application in photocatalysis. The final surface area of the particles was - 100 m2 g(-1), and their photocatalytic efficiency matched that of P25 TiO2.