Facile synthesis of V⁴⁺self-doped, [010] oriented BiVO₄nanorods with highly efficient visible light-induced photocatalytic activity

Abstract

Monodispersed monoclinic BiVO4 nanorods grown along the [010] direction were prepared using a one-step low temperature hydrothermal method in the presence of the low-cost, nontoxic sodium oleate serving as a chelating agent. The BiVO4 nanorods with diameters of 15-20 nm possess a huge specific surface area as large as 28.2 m(2) g(-1), which can endow them with high photocatalytic activity and strong adsorption of reactants. Meanwhile, the specific [010] growth direction is capable of facilitating efficient electron-hole separation by accumulating electrons on {010} facets. Thus, the highly efficient photocatalytic activity of the as-prepared BiVO4 nanorods under visible light, which far surpasses that of commercial P25, is demonstrated by the degradation of rhodamine B and phenol. Plentiful V(4+) species, which can create oxygen vacancies, is detected implying that the as-obtained nanorods are self-doped BiVO4. Significantly, 61% of rhodamine B is adsorbed by the BiVO4 nanorods before irradiation owing to the appearance of plentiful O(2-) and OH(-) species on the surface adsorbed by oxygen vacancies. More excitingly, the excellent visible-light-driven photocatalytic activity of the as-obtained BiVO4 nanorods can be further elevated to an unprecedented level, roughly doubled, after applying a low temperature heat treatment process at 230 °C for 2 h and this improvement could primarily be ascribed to their optimized charge-carrier transport characteristics resulting from elevated crystallinity and decreased V(4+) species.

Synthesis of a monoclinic BiVO4 nanorod array as the photocatalyst for efficient photoelectrochemical water oxidation

“…14 The calculated oxidation potential may be more negative than the calculated valance edge of the material, as veried by the previous literature. 14 Hence, great efforts have been made to improve the photocatalytic properties of BiVO 4 , e.g., developing heterojunctions, [15][16][17] designing morphologies, [18][19][20][21][22] doping ions, [23][24][25] and facet selective deposition. 26,27 The morphology design is the most commonly used way to improve the electron transfer of BiVO 4 photocatalysts.…”

An Electrochemically Treated BiVO4 Photoanode for Efficient Photoelectrochemical Water Splitting

“…However,e xcessive V 4+ is detrimental to the PEC performance of BiVO 4 ,b ecause larger radius of V 4+ acts as scattering centers and reduce the diffusion length of holes. [14] Obviously,i ti sv ery challenging to tune the content of V 4+ to achieve efficient BiVO 4 photoanodes via hydrogenation or chemical reduction. Note that hydrogenation requires pure H 2 flowing at high temperature, [12] which would increase the fabrication hazard and cost as well.…”

Ru Nanoparticles Supported on Oxygen‐Deficient 3DOM BiVO4: High‐Performance Catalysts for the Visible‐Light‐Driven Selective Oxidation of Benzyl Alcohol

“…This result can be explained by existence of oxygen vacancies resulted from the change in local coordination environments of Bi 3 + and V 5 + (thus generating V 4 + species). [33][34][35] The O 1s signal of each sample was decomposed into three components at BE = 529.7-530.0, 531.0-531.3, and 532.9-533.1 eV, attributable to the surface lattice oxygen (O latt ), adsorbed oxygen (O ads ), and adsorbed water species, respectively. [36] We can observe from Figure S3 that the O ads concentration increased with the rise in Ru loading of Ru/3DOM BiVO 4 .…”