Enhanced adsorption and degradation of methylene blue over mixed niobium-cerium oxide – Unraveling the synergy between Nb and Ce in advanced oxidation processes

Formation of reactive oxygen species (ROS) via H2O2 activation is vital importance in catalytic environmental chemistry, especially degradation organic pollutants. A new mixed niobium-cerium oxide (NbCeOx) was tailored for this purpose. thorough structural and chemical characterization NbCeOx along with CeO2 Nb2O5 reference materials carried out using TEM/STEM/EDS, SEM, XRD, XPS, EPR, UV–vis N2 physisorption. The ability the catalysts to activate towards ROS formation assessed on basis EPR Raman measurements. Catalytic activity oxides evaluated methylene blue (MB) as a model pollutant. Very high attributed redox-acidic nature its surface, which originated from synergy between Nb Ce species. These two properties (redox acidity) ensured convenient conditions efficient MB. MB found 3 times higher than that commercial CBMM catalyst 240 CeO2. mechanism reaction be an adsorption-triggered process initiated by hydroxyl radicals, generated surface transformation O2–•/O22–.