Phenyl Hypophosphorous Acid‐Assisted Synthesis of Carbon‐Modified Anatase‐Brookite Bicrystal TiO₂ Nanoparticles with Enhanced Visible‐Light Photocatalytic Performance

Abstract

Carbon‐modified anatase‐brookite bicrystal TiO2 nanoparticle (C/TiO2) photocatalysts were successfully synthesized by a facile hydrothermal method using phenyl hypophosphorous acid (PA) as a ligand to mediate the physicochemical properties and as a source of carbon. The carbon species were in situ formed and loaded on TiO2 surface via carbonization of PA. The characterization results show that the morphology, phase structure, crystal size, chemical states of elements and photocatalytic activity of the C/TiO2 vary with the amount of PA used. The photocatalytic performance of C/TiO2 is significantly improved compared with pure TiO2 because (1) carbon decoration of TiO2 surface extends the light absorption to the visible‐light range; (2) charge transfer between anatase and brookite nanocrystals increases the quantum efficiency; and (3) small C/TiO2 nanocrystals yield stronger adsorption capability resulting in an increase in photocatalytic activity. Visible‐light photocatalytic degradation of methyl orange (MO) by the C/TiO2 photocatalyst was successfully achieved. The MO concentration was reduced by 78 % after exposure to visible light for 180 min. The C/TiO2 photocatalyst was highly stable after four successive experimental runs.

2D@0D Multidimensional Nanoparticles for Improving the Fire Safety of Epoxy Resin

“…43 Meanwhile, in the Ti 2p spectrum of the external burning residue of EP/ 8WC@TDP, the peaks at 459.6 and 465.4 eV were assigned to the characteristic peaks of TiO 2 . 44 The Ti, W, and P contents in the external char were higher than those in the internal char, indicating that TiO 2 , WS 2 with a small part of WO 3 , and substances containing phosphorus were transferred (migrated) to the surface of the char during burning.…”

“…Compared with that of bulk WS 2 , the characteristic peaks in the W 4f spectra of WC and WC@TDP shifted in the lowerbinding energy direction as a result of the surface modifications of chitosan and TDP, respectively. As shown in Figure 3b, the fitted O1 s peaks of WC@TDP located at 530.1 and 531.4 eV contributed to Ti−O−Ti and Ti−O−P, 44 respectively, and the binding energies of the corresponding peaks were lower than that of TDP because of the noncovalent interaction between TDP and WC. In addition, the peak at 533.0 eV was attributed to the absorbed H 2 O on the surface of WC@TDP.…”