Metal-Organic Framework-Templated Synthesis of Bifunctional N-Doped TiO2-Carbon Nanotablets via Solid-State Thermolysis

Yuqiao Gu , K. Cheng , Y.-N. Wu , Y. Wang , C. Morlay (1) , F. Li

1 MATEIS - Matériaux, ingénierie et science [Villeurbanne]

Porous nitrogen-doped TiO2-carbon hybrid nanotablets were prepared via one-step solid-state thermolysis of amino-functionalized titanium metal-organic framework NH2-MIL-125(Ti). Amorphous, anatase, rutile, or mixture phases of TiO2 were obtained controllably by manipulating pyrolysis temperature. The anionic N- in NH2-MIL-125(Ti)’s 3D structure formed as pyridinic nitrogen and pyrrolic nitrogen into the graphene layer. Meanwhile, a programmed evolution of the porous structure of the resultant composites, i.e., microporous, hierarchically micro/mesoporous, and mesoporous, was presented systematically. The morphology and specific nanoporous structure of the products are conferred by the metal-organic framework template. The resultant composites with hierarcical meso/miciroporous structures showed highly improved CO2 uptake ability compared with those of commercial P25 TiO2, g-C3N4, and 3D graphene. TiO2 nanoparticles are well dispersed in the porous nitrogen-doped carbon matrix, endowing the obtained composites with effective photocatalytic activity. The nitrogen-doped TiO2-carbon nanotablets with hierarchically micro/mesoporous structure and anatase/rutile heterostructure exhibited the best photocatalytic performance with excellent adsorption capacity toward organic dyes. Results also indicated that the optimized composite possessed excellent long-term stability and regeneration ability. Benefiting from their versatile pore structure, heteroatom doping, and semiconductor incorporation, the nitrogen-doped TiO2-carbon composites derived from metal-organic frameworks could find various potential applications, especially for sustainable chemistry and engineering. © 2016 American Chemical Society.

Mots clés: Carbon carbon composites; Carbon dioxide; Crystalline materials; Graphene; Heterojunctions; Mesoporous materials; Metals; Nitrogen; Organic polymers; Organometallics; Oxide minerals; Semiconductor doping; Thermolysis; Titanium dioxide; Adsorption capacities; Metal organic framework; Nitrogen-doped carbons; Photocatalytic activities; Photocatalytic performance; Pyrolysis temperature; Solid state thermolysis; Sustainable chemistry; Doping (additives)

Domaines: Matériaux

Yuqiao Gu, K. Cheng, Y.-N. Wu, Y. Wang, C. Morlay, et al.. Metal-Organic Framework-Templated Synthesis of Bifunctional N-Doped TiO2-Carbon Nanotablets via Solid-State Thermolysis. ACS Sustainable Chemistry & Engineering, 2016, 4 (12), pp.6744-6753. ⟨10.1021/acssuschemeng.6b01716⟩. ⟨hal-01804525⟩