Preparation and Characterization of Freestanding Hierarchical Porous TiO2 Monolith Modified with Graphene Oxide

Abstract

Catalyst recovery is one of the most important aspects that restrict the application of TiO2 photocatalyst. In order to reduce restrictions and improve the photocatalytic efficiency, a hierarchical porous TiO2 monolith (PTM) with well-defined macroporous and homogeneous mesoporous structure was prepared by using a sol-gel phase separation method. P123 was used as the mesoporous template and graphene oxide was applied to increase the activity and integrity of the monolithic TiO2. According to scanning electron microscopy and the Barrett-Joyner-Halenda measurements, PTM3 is mainly composed of 10 nm anatase crystallines with 3.6 nm mesopores and 2-8 μm macropores. Further characterization suggests carbon and nitrogen have been maintained in the PTM during calcinations so as to induce the visible light activity. The PTM with 0.07 wt% graphene oxide dosage shows high efficiency for methyl orange (MO) decolorization under both full spectrum and visible light irradiation (λ >400 nm). Besides, the monolith remains intact and has good photocatalytic stability after four cyclic experiments.

Enhanced Photocatalytic Activity of Nanoparticle-Aggregated Ag–AgX(X = Cl, Br)@TiO2 Microspheres Under Visible Light

“…As an important photocatalyst, titanium dioxide (TiO 2 ) has been widely used in decomposition of toxic and hazardous organic pollutants, and in water splitting for hydrogen production [ 1 – 3 ]. However, the rapid recombination of photoinduced electrons and holes and its wide band gap greatly lower the TiO 2 quantum efficiency.…”

Binder-Free TiO2 Monolith-Packed Pipette Tips for the Enrichment of Phosphorylated Peptides

“…block polymer surfactants) have been used to prepare porous TiO 2 monoliths. [14,15] However, in most cases, prepacking of templates is necessary. The use of APF spheres as templates allows a convenient synthesis of macroporous TiO 2 monolith with a uniform pore size.…”

The Synergistic Effect of Pyridinic Nitrogen and Graphitic Nitrogen of Nitrogen-Doped Graphene Quantum Dots for Enhanced TiO2 Nanocomposites’ Photocatalytic Performance

“…Although it has so many superior properties, use of TiO 2 as a photocatalyst is limited by some disadvantages in practical application, such as a wide band gap (3.2 eV) and a high electron-hole recombination rate, which leads to low photocatalytic efficiency [3,[9][10][11]. To perfect the photocatalytic activity of TiO 2 , various measures were utilized, such as many ions being doped into the lattice of TiO 2 [12], sensitization via absorbed molecules [13][14][15], compound with other materials [16,17], and the surface being coated with other cocatalysts possessing excellent performance [18][19][20][21]. Among the methods mentioned above, surface loading with other cocatalysts is relatively facile and effective in enhancing the photocatalytic activity of TiO 2 .…”