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The design and synthesis of highly efficient and low-temperature NO x reduction catalysts with long-term stability and good water resistance still remain a challenge in the field of gas catalysis. In this work, we demonstrated the integration of MnO x -Fe 2 O 3 /TiO 2 /Ti monolithic catalysts on flexible Ti mesh through plasma electrolytic oxidation technology, associated with hydrothermal reaction, and chemical bath deposition methods. The in-situ grown TiO 2 nanosheet supports hold a very strong substrate adhesion with Ti mesh, and provide ideal nucleation sites for the following deposition of high density of MnO x -Fe 2 O 3 active components. The brush-like nanostructure morphology of active MnO x -Fe 2 O 3 catalysts enables the complete adsorption and reaction of gas molecules on the catalyst surface. The selective catalytic reduction of NO x with NH 3 tests indicate that MnO x -Fe 2 O 3 /TiO 2 /Ti monolithic catalysts exhibit excellent low-temperature catalytic performance with 100% of NO x conversion at 137 °C, good stability and water resistance, showing great potential and broad application prospects in comparison with powder catalysts and honeycomb ceramic catalysts. The strategy of depositing multi-components active catalysts on in-situ grown ultra-thin TiO 2 nanosheet supports on flexible Ti mesh paves a solid way toward the practical applications of novel low-temperature selective catalytic reduction catalysts in diverse fields. [Display omitted] • TiO 2 nanosheet array in-situ grown on the Ti mesh serves as ideal substrate for Mn-Fe active component deposition. • Needle-like MnO x -Fe 2 O 3 heterostructure nanowires have large surface area and strong synergistic effect. • MnO x -Fe 2 O 3 /TiO 2 /Ti monolithic catalysts exhibit excellent low-temperature catalytic performance and good stability. [ABSTRACT FROM AUTHOR]

Transition metal oxide catalysts have attracted considerable attention for their promising potential as an alternative to replace noble metal catalysts in the application of various catalytic reactions. Herein, we report the design of monolithic Mn 3 O 4 /TiO 2 catalysts in-situ grown on Ti mesh substrate for efficient and stable CO oxidation. Porous TiO 2 film which is fabricated from the oxidation of Ti mesh using conventional plasma electrolytic oxide process plays an important role in the in-situ nucleation of TiO 2 nanosheets with strong adhesion to maintain the long-term stable CO oxidation, as well as providing Ti precursors for the formation of TiO 2 nanosheets. The decoration of Mn 3 O 4 co-catalysts on TiO 2 nanosheet support could significantly enhance the catalytic property of monolithic Mn 3 O 4 /TiO 2 catalysts due to the synergetic effect. Thus, a complete CO oxidation can be achieved as low as 160 °C without the involvement of any noble metal catalyst. The novel synthesis strategy of Mn 3 O 4 /TiO 2 heterogeneous catalysts shows overwhelming advantages of outstanding catalytic performance and superior stability in comparison with other traditional methods of powder-based catalysts. More importantly, it can be extended to the rational design of a variety of TiO 2 -based transition metal oxide catalysts which can be used for diverse applications including CO oxidation, de-NO x , CH x decomposition etc. Image 1 • In-situ grown TiO 2 seeding layer with strong adhesion is fabricated on Ti mesh by PEO method. • Mn 3 O 4 cocatalyst is uniformly supported on TiO 2 nanosheets grown on TiO 2 film. • Mn 3 O 4 /TiO 2 monolithic catalysts show low-temperature and stable CO oxidation performance. • Mn 3 O 4 /TiO 2 monolithic catalysts on flexible Ti mesh is promising for a variety of catalytic applications. [ABSTRACT FROM AUTHOR]