Controlling the dispersion of Co₃O₄ nanoparticles inside mesoporous nanorattle catalysts

Here we report a simple method to synthesize cobalt nanoparticles inside mesoporous nanorattle catalysts. In this method, zeolitic imidazolate framework ZIF-67 is used as structural template for the preparation of a mesoporous metal oxide shell as well as sacrificial precursor to form cobalt nanoparticles inside the shell. Furthermore, we demonstrate that the introduction of a carbonization step prior to the final calcination can decrease the required calcination temperature from 550 °C to 300 °C. This has a large effect on the dispersion and catalytic activity of Co₃O₄ for CO oxidation and decreases the light-of temperature (temperature at 50% conversion) from 160°C to 134°C. Exploiting metal-organic frameworks as both structural template and sacrificial precursor offers precise control of size, shape and structure and opens up new exiting opportunities for design of advanced nanostructured catalysts.