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Ag-TiO 2-x (B)/g-C 3 N 4 ternary heterojunctions photocatalysts are fabricated by hydrothermal-calcination, photo-deposition procedure, and followed by in-situ solid-state chemical reduction procedure. As-obtained photocatalysts are consisted with heterojunctions between 2D g-C 3 N 4 sheets and 1D TiO 2 (B) single-crystalline nanorods. The band gap of Ag-TiO 2-x (B)/g-C 3 N 4 ternary heterojunctions photocatalysts is reduced to ∼2.23 eV due to plasma Ag and surface engineering. Under visible light irradiation, it has an optimal photocatalytic property for the reduction of Cr 6+ (95%) and degradation of NH 4 + (93%). The apparent reaction rate constants (k) of ternary heterojunctions photocatalysts for NH 4 + and Cr 6+ are 25 and 12 folds higher than that of original TiO 2 (B). Furthermore, Ag-TiO 2-x (B)/g-C 3 N 4 also has excellent hydrogen production efficiency, which is up to 410 µmol h -1  g -1 . This enhancement can be attributed to the unique heterojunction formed by 1D single-crystalline TiO 2 (B) nanorods and 2D g-C 3 N 4 sheets, surface plasma resonance effect of plasma Ag nanoparticle, and surface engineering. A possible photocatalytic mechanism is also proposed by analysizing the XPS valence-band spectra and the Mott-Schottky., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Plasmon Ag decorated 3D urchinlike N-TiO 2-x photocatalysts are successfully synthesized by a facile hydrothermal treatment (180 °C) and combined with a photo-deposition approach, followed by a reduction treatment. The results show that the resultant Ag/N-TiO 2-x sample possesses a three-dimensional (3D) urchinlike nanostructure with high crystallinity of anatase. Meanwhile, it exhibits the narrow optical band gap (Eg ∼ 2.61 eV) and the excellent visible-light-driven photocatalytic performance. Moreover, the hydrogen generation rate and photocatalytic degradation rate of phenol are up to 186.2 μmol h -1  g -1 and 97.7% under visible light irradiation, which are about 4.2 and 5.4 folds greater than that of N-TiO 2 . The mechanism of photocatalytic process is also proposed, and the enhanced photocatalytic property is mainly due to the synergistic reaction of the Ti 3+ and N codoping, which narrows the band gap and favors the utilization of visible light, and the plasmon effect of Ag nanoparticles and unique 3D urchinlike architecture, which are propitious to the separation and transmission of photogenerated carriers., (Copyright © 2018 Elsevier Inc. All rights reserved.)