0000000000246165
AUTHOR
Eva Pütz
Nanocomposite antimicrobials prevent bacterial growth through the enzyme-like activity of Bi-doped cerium dioxide (Ce1−xBixO2−δ)
Preventing bacterial adhesion on materials surfaces is an important problem in marine, industrial, medical and environmental fields and a topic of major medical and societal importance. A defense strategy of marine organisms against bacterial colonization relies on the biohalogenation of signaling compounds that interfere with bacterial communication. These reactions are catalyzed by haloperoxidases, a class of metal-dependent enzymes, whose activity can be emulated by ceria nanoparticles. The enzyme-like activity of ceria was enhanced by a factor of 3 through bismuth substitution (Ce1−xBixO2−δ). The solubility of Bi3+ in CeO2 is confined to the range 0 < x < 0.25 under quasi-hydrothermal c…
Selective Synthesis of Monodisperse CoO Nanooctahedra as Catalysts for Electrochemical Water Oxidation
Thermal decomposition is a promising route for the synthesis of metal oxide nanoparticles because size and morphology can be tuned by minute control of the reaction variables. We synthesized CoO nanooctahedra with diameters of ∼48 nm and a narrow size distribution. Full control over nanoparticle size and morphology could be obtained by controlling the reaction time, surfactant ratio, and reactant concentrations. We show that the particle size does not increase monotonically with time or surfactant concentration but passes through minima or maxima. We unravel the critical role of the surfactants in nucleation and growth and rationalize the observed experimental trends in accordance with simu…