Controllable synthesis of SrCO3 with different morphologies and their co-catalytic activities for photocatalytic oxidation of hydrocarbon gases over TiO2

The controlled synthesis of strontium carbonate (SrCO3) micro-/nanostructures with various morphologies, such as sphere, pompon, arborization, spindle, and hexagonal prism, are successfully achieved through rather facile hydrothermal processes. The morphology of SrCO3 can be elegantly adjusted by employing different CO3 (2-) sources and controlling the viscidity of the organic solvents. The underlying mechanism of morphology evolution is discussed. Moreover, the SrCO3-loaded TiO2 (SrCO3/TiO2) nanocomposites are shown to improve the activity for oxidizing hydrocarbon gases under simulated solar light irradiation. The 5.0 wt% SrCO3 (nanosphere)/TiO2 exhibited the highest performance toward the oxidation of the hydrocarbons gases, and its activity on methane oxidation is more than double that of P25 TiO2. These results are valuable for both carbonate synthesis and their use in the oxidation of hydrocarbons gases.