One-step topological preparation of carbon doped and coated TiO₂ hollow nanocubes for synergistically enhanced visible photodegradation activity

Abstract

a Various three-dimensional TiO 2 hollow structures have attracted strong scientific and technological attention due to their excellent properties. 3D hierarchical TiO 2 hollow nanocubes (TiO 2 -HNBs) are not good candidates for industrial photocatalytic applications due to their large energy gap which is only activated by UV light. Herein, visible-light-responsive carbon doped and coated TiO 2 -HNBs (C@TiO 2 -HNBs) with a dominant exposure of {001} facets have been prepared via a template-engaged topotactic transformation process using facile one-step solvothermal treatment and a solution containing ethanol, glucose and TiOF 2 . The effects of reaction time and glucose/TiOF 2 mass ratio on the structure and performance of C@TiO 2 -HNBs were systematically studied. We found that glucose played an important role in providing H 2 O during the topological transformation from self-templated TiOF 2 cubes into 3D hierarchical TiO 2 hollow nanocubes versus dehydration reactions, where its main function was as a carbon source. Coated carbon was deposited predominantly on the surface as sp 2 graphitic carbon in extended p conjugated graphite-like environments, and doped carbon mainly replaced Ti atoms in the surface lattice to form a carbonate structure. The results were confirmed using TEM SEM, EDS, XRD, FT-IR, XPS and Raman spectroscopic studies. The C@TiO 2 -HNBs achieved greatly improved RhB photodegradation activity under visible light irradiation. The catalyst prepared with glucose/TiOF 2 at a mass ratio of 0.15 (T24-0.15) showed the highest photodegradation rate of 96% in 40 min, which is 7.0 times higher than those of the TiO 2 -HNBs and P25. This new synthetic approach proposes a novel way to construct carbon hybridized 3D hierarchical TiO 2 hollow nanocubes by combining two modification methods, "element doped" and "surface sensitized", at the same time.

Biomolecules encapsulated TiO2nano‐cubes usingTinospora cordifoliafor photodegradation of a textile dye

“…Similar type of morphology for silver nanoparticles has been reported earlier using Eucalyptus macrocarpa leaf extract [12]. A dark black layer on nano-cubes is noticed which ascribes the accumulation of carbon on TiO 2 surface [13]. It is well in agreement with EDX results.…”

Highly crystalline anatase TiO2 nanocuboids as an efficient photocatalyst for hydrogen generation

“…The band at 1659 cm À1 for TiO 2 Ncs prepared at 200 C for 48 h can be attributed to the O]C-O-Ti bond of the carbonate structure, further conrming that doped carbon substituted surface Ti atoms to form a carbonate structure, while the band at 1645 cm À1 for commercial TiO 2 is due to the O-H bending vibrations of the adsorbed water molecules. 82,83 The band at 1535 cm À1 is assigned to the N-H in-plane bending vibration and C-N stretching vibration and the band at 1179 cm À1 is due to C-N stretching. 84 No such nitrogen related bands are observed for commercial TiO 2 , suggesting that the N species have been incorporated into the lattice of TiO 2 nanocuboids.…”

Organic Species-Intercalated Vanadium Oxide for Sodium-Ion Battery: Mixed-Anion Coordination Effect, Enhanced d-p Orbital Hybridization, and Topotactic Phase Conversion Induced by N-Substitution

“…The similar structure of Na x V 2 O 5 and ( p -TQ)-VN, d (00 l ) (Na x V 2 O 5 ) = d (00 l ) (( p -TQ)-VN) indicates the partial topotactic phase transformation of ( p -TQ)-VN → Na x V 2 O 5 (Figure d,e). Topotactic phase transformation means that the involved two phases are matched in a lattice, which enables structural transition without remarkably changing the crystalline symmetry or principal framework of the parental phase, leading to the reversible (de)­intercalation of Na + during the charge/discharge process. − …”