Z-scheme reduced graphene oxide/TiO2-Bronze/W18O49 ternary heterostructure towards efficient full solar-spectrum photocatalysis

Z-scheme reduced graphene oxide (rGO)/TiO 2 -bronze (TiO 2 -B)/W 18 O 49 photocatalyst consisted of rGO, super-thin TiO 2 -B nanosheets , and W 18 O 49 nanofibers was fabricated by a two-step solvothermal synthesis route. The TiO 2 -B nanosheets were tightly attached on rGO firstly. W 18 O 49 nanowires were then grown on rGO/TiO 2 -B. Precursors and reaction conditions play important roles for getting the optimal microstructure. The ternary photocatalyst is able to absorb sunlight ranging from ultraviolet to near infrared regions , which makes full use of light for efficiently photocatalytic degrading organic pollutants. The light absorption intensity and photon-generated carrier transfer efficiency are both improved with adding rGO. The localized surface plasmon resonance effect arose from the nonstoichiometric W 18 O 49 is in favour of the absorption range of the rGO/TiO 2 -B/W 18 O 49 composite broadening to near infrared light range. The photocatalytic mechanism of Z-scheme rGO/TiO 2 -B/W 18 O 49 composite was verified by an electron spin resonance test. The conduction band of TiO 2 -B and the valence band of W 18 O 49 are used in the photocatalytic degradation of rhodamine B, facilitating the efficient separation of photogenerated carriers . The rGO/TiO 2 -B/W 18 O 49 heterostructure exhibits an excellent photocatalytic performance under full solar-spectrum irradiation. The result may represent a new strategy for the construction of nanocomposites with suitable band structure in the efficient application of full solar light.