Assembling core-shell SiO2@NiaCobOx nanotube decorated by hierarchical NiCo-Phyllisilicate ultrathin nanosheets for highly efficient catalytic combustion of VOCs

Configuring Ni-based catalyst with superior activity and stability is one efficient strategy in achieving its application for VOCs catalytic combustion. Here, we report the rational design and synthesis of core-shell SiO 2 @Ni a Co b O x nanotube derived from three-layered C@SiO 2 @NiCo-Phyllosilicate nanofiber. Through a typical hydrothermal strategy, the hierarchical NiCo-Phyllosilicate ultrathin nanosheets are fitly grown on the surface of order mesoporous SiO 2 nanotube, which is obtained through thermal treatment of core-shell C@SiO 2 nanofiber in air. Whereafter, a core-shell SiO 2 @Ni 2 Co 1 O x nanotube is obtained to achieve the highly efficient conversion of VOCs in the presence of 5vol%H 2 O. We observe this special structural design can own superior redox ability, provide active oxygen species (O ads ), and generate the abundant acid sites. Ideally, the low-temperature catalytic combustion of toluene over the core-shell SiO 2 @Ni 2 Co 1 O x nanotube is realized through the combined action of Marse-van Krevelen (MvK) and Langmuir-Hinshelwood (L-H) mechanism. Simultaneously, a good thermal stability and water resistance is also achieved, which benefits from the guided growth of order mesoporous SiO 2 nanotube, the presence of strong interactions (Ni-O-Si band) and the contribution of surface -OH groups in the special “fibrous” structure of phyllosilicate. A core-shell SiO 2 @Ni a Co b O x nanotube is prospectively obtained to achieve the highly efficient catalytic combustion of toluene in the presence of 5 vol% H 2 O. We observe this special structural design can own superior redox ability, provide active oxygen species (O ads ), and generate the abundant weak acid sites. Ideally, the superior activity for toluene catalytic combustion over the core-shell SiO 2 @Ni 2 Co 1 O x nanotube is realized through the synergistic promotion of adsorbed oxygen (O ads ) from Co &+ species and lattice oxygen (O latt ) from Ni &+ species. • Core-shell SiO2@Ni2Co1Ox nanotube was successfully constructed. • Core-shell SiO2@Ni2Co1Ox nanotube owns superior redox ability, rich oxygen species and weak acid sites. • The synergistic promotion of Oads and Olatt was proposed. • An improved water resistance may be ascribed to the contribution of surface OH groups.