In situ growth of TiO₂ nanocrystals on g-C₃N₄ for enhanced photocatalytic performance

Abstract

Well dispersed TiO2 nanocrystals with (001) facets were successfully grown in situ on g-C3N4 through a facial solvothermal method. The resultant TiO2/g-C3N4 composites exhibit remarkably higher efficiency for photocatalytic degradation of phenol as compared to pure catalysts (g-C3N4 or TiO2) or mechanically mixed TiO2/g-C3N4. The optimal composite with 11.2 wt% TiO2 showed the highest degradation rate constant, which is 2.8 times that of pure g-C3N4, 2.2 times that of pure TiO2, and 1.4 times that of mechanically mixed TiO2/g-C3N4. The enhanced photocatalytic activity is mainly attributed to the effective charge separation derived from two aspects: (1) well matched energy levels between TiO2 and g-C3N4 and (2) a uniform and close contact between TiO2 and g-C3N4 that resulted from the in situ growth of highly dispersed TiO2 nanocrystals. The TiO2/g-C3N4 hybrid material prepared in this study is expected to provide a good foundation for the further design and synthesis of advanced TiO2/g-C3N4-based functional materials, and the in situ growth method developed is hopeful to provide a new strategy for the synthesis of other semiconductor-modified g-C3N4 materials.

TiO2/g-C3N4 nanosheets hybrid photocatalyst with enhanced photocatalytic activity under visible light irradiation

“…Colón et al [28] reported the preparation of g-C 3 N 4 -TiO 2 composites with different g-C 3 N 4 loadings by simple impregnation, giving good photoactivity for the degradation of phenol under UV irradiation. Zhang et al [29] has found that well-dispersed TiO 2 nanocrystals with (001) facets prepared in situ on g-C 3 N 4 through a facile solvothermal method exhibit higher efficiency for photocatalytic degradation of phenol as compared to pure g-C 3 N 4 and TiO 2 or mechanically mixed TiO 2 /g-C 3 N 4 . Therefore, combining TiO 2 with g-C 3 N 4 to form composite photocatalysts seems to be an effective approach to construct a heterojunction structure leading to enhanced photoactivity.…”

BiVO4‐TiO2 Composite Photocatalysts for Dye Degradation Formed Using the SILAR Method

“…However, the activity of TiO2 is hindered by two factors; a wide band gap which restricts its activity to only UV light, and fast charge recombination leading to few surface reactions occurring. Much work has been devoted to overcoming both these problems including tuning the nanostructure of TiO2 itself [8][9][10] , doping with non-metals [11][12][13] , metals 14 and combinations of two [15][16][17] or even more 18 dopants, introduction of plasmonic metal nanoparticles 19,20 and formation of nanocomposites with conductive organic nanomaterials 21,22 . Furthermore, two or more of these methods are often combined to produce high activity photocatalysts 23 .…”

Tailoring TiO2 Nanotube‐Interlaced Graphite Carbon Nitride Nanosheets for Improving Visible‐Light‐Driven Photocatalytic Performance

“…Among various routes, the introduction of an appropriate band structure at the heterojunction interface is the most important prerequisite to enhance the charge separation efficiency for increasing photocatalytic performance. [[qv: 9a,12a,15]] Since TiO 2 has an advantage in electron–hole separation for its special energy band,16 the establishment of heterostructure between g‐C 3 N 4 and TiO 2 is an effective way to improve the efficiency of charge separation in g‐C 3 N 4 /TiO 2 photocatalyst systems 17. 1D TiO 2 nanotubes having the advantage of intimate contact with 2D nanosheets and cross‐linked network18 present a significant potential as photoinduced electron sink in g‐C 3 N 4 /TiO 2 heterojunction hybrids for the electron–hole separation.…”