Hollowsphere Nanoheterojunction of g-C₃N₄@TiO₂ with High Visible Light Photocatalytic Property

Abstract

In this work, g-C3N4@TiO2 nanostructures with hollow sphere morphology, small grain size, high crystalline quality, and high surface area are successfully synthesized by the annealing method using melamine and hollowsphere precursor, which could be a universal method to synthesis hollow sphere nanoheterojunction. Excellent photocatalytic property was observed from the as-prepared g-C3N4@TiO2 nanostructure with 466.43 μmol·g–1·h–1 hydrogen generation rate under visible light irradiation (>420 nm), which was 5.5 times as much as the control couple, nanoparticle nanoheterojunction g-C3N4@TiO2. No apparent deactivation was found during the follow-up cycle performance test. The special morphology and the heterojunction construction contribute to both visible light absorption and photogenerated electron–hole pair separation efficiency and finally to the photocatalytic property. The content of g-C3N4 was proved to be an important parameter for the promotion of the photocatalytic property. Overlarge content may lead to lower photogenerated electron–hole pair separation efficiency.

Solvothermal preparation and tribological performance of g‐C 3 N 4 /TiO 2 hybrids as oil‐based lubricant additives

“…21‐1272), which is consistent with previous references [30, 31]. Furthermore, the presence of characteristic peaks of g‐C 3 N 4 and TiO 2 in the g‐C 3 N 4 /TiO 2 system can be easily obtained simultaneously [32, 33]. Moreover, no other impurity substance was detected, suggesting that TiO 2 is well combined with g‐C 3 N 4 with high chemical purity.…”

“…Moreover, the high-resolution spectrum of N 1s (Fig. 3c) is split into three peaks located at 398.62, 399.55 and 400.68 eV, which belongs to C=N-C, N-(C) 3 and C-N-H groups [32][33][34], separately. Therefore, XPS data together with those from the XRD can be concluded the fabrication of binary system g-C 3 N 4 /TiO 2 .…”

Heterostructured g-CN/TiO2 Photocatalysts Prepared by Thermolysis of g-CN/MIL-125(Ti) Composites for Efficient Pollutant Degradation and Hydrogen Production

“…These results further demonstrate that the heterojunction constructed between TiO 2 and g-CN combined to the high specific surface of the catalyst contribute to the enhancement of photogenerated electron transfer and thus to the photocatalytic activity. Finally, the photocatalytic activity for H 2 production is at least 2.6-times higher than that of binary g-CN/TiO 2 catalyst recently described in the literature (the highest HER values vary from 446 to 500 µmolh −1 g −1 ) [18,25,32,33]. Noteworthy is also that some higher values were reported (up to 8931 µmolh −1 g −1 ) but using Pt as co-catalyst [22].…”

“…To improve the interfacial connection between TiO 2 and g-CN and thus the delocalization of charge carriers, synthetic methods involving the deposition of Ti precursors like Ti(On-Bu) 4 at the surface of exfoliated g-CN followed a hydro-or a solvothermal reaction and a calcination have been reported [22][23][24][25]. The reverse process including the generation of g-CN by calcination of N-rich precursors (melamine and/or cyanuric acid) in the presence of TiO 2 nanoparticles or titanate nanotubes has also been investigated [26][27][28][29][30][31][32]. Finally, the vapor phase deposition of g-CN at the surface of TiO 2 [33] or the surface modification of g-CN with chloroacetic acid to increase the association with TiO 2 have also been reported [34].…”

Carbon Sphere Template Derived Hollow Nanostructure for Photocatalysis and Gas Sensing

“…The photogenerated electrons and holes will be separated into the conduction band of ZnO and valence band of ZnFe 2 O 4 by the built-in electric field, respectively, thereby minimizing the recombination and boosting the photocatalytic H 2 generation performance of samples. Meanwhile, Li et al [81] have reported a high-crystallinity g-C 3 N 4 /TiO 2 hollowsphere nanoheterojunction photocatalyst with large surface area through a carbon sphere templating method. By carefully tuning the ratio of precursors, the optimum g-C 3 N 4 /TiO 2 photocatalyst obtain a 5.5-fold enhancement in visible-light-driven hydrogen generation rate, reaching almost 470 µmol g −1 h −1 .…”