The precursor-guided hydrothermal synthesis of CuBi2O4/WO3 heterostructure with enhanced photoactivity under simulated solar light irradiation and mechanism insight.

Photoelectrochemical properties of iron-cobalt WTiO2 nanotube photoanodes for water splitting and photocathodic protection of stainless steel

Novel 1D Bi4O5I2 hollow nanotube (Bi4O5I2-HNT) material has been controlled synthesized via a facile PVP-assisted solvothermal method for the first time. Different parameters to control the formation of Bi4O5I2-HNT were tuned, such as usage amount of PVP, reaction temperature and mannitol concentration. Furthermore, structure, surface chemical composition, optical absorption ability and photogenerated charge separation efficiency of as-prepared Bi4O5I2 nanosheet and Bi4O5I2-HNT samples have been measured. Benefiting from the specific ultrathin hollow nanotube structure to produce confined highly concentrated active species and excellent electrical conductivity, Bi4O5I2-HNT material exhibited the increased photocatalytic degradation performance towards bisphenol A relative to Bi4O5I2 nanosheet. This work opens the door for designing other Bi-based photocatalysts via facile soft-template-assisted method to achieve a high-efficient photocatalytic performance.

Confined active species and effective charge separation in Bi4O5I2 ultrathin hollow nanotube with increased photocatalytic activity

The nanotube array-like WO3 (WA) photoanode has been widely utilized in solar-driven photoelectrocatalytic applications due to its excellent light absorption. However, it still suffers from a low quantum efficiency. Herein, double oxygen-evolution catalyst (OEC) layers (FeOOH and NiOOH) were deposited onto the surface of WA with the formation of a WA-FeOOH/NiOOH photoanode (WA-FeNi). The FeOOH greatly decreased the WA/OEC interfacial electron–hole pair recombination rate, while the NiOOH reduced the OEC/electrolyte interfacial electron–hole pairs recombination and promoted the composite’s water oxidation activity significantly. The as-formed WA-FeNi photoanode possessed a photocurrent density of 120 μA/cm2 under simulated sunlight irradiation, which is almost 200% that of WA. The electron–hole separation yield at 0.6 V versus SCE in the former was determined to be 39.3%, which is nearly 2.5 times that of the latter. As a result, the photoanode exhibited superstrong simulated-sunlight-driven photoelectroca...

Nanotube Array-Like WO3 Photoanode with Dual-Layer Oxygen-Evolution Cocatalysts for Photoelectrocatalytic Overall Water Splitting

Carbon quantum dots (CQDs) modified TiO2 nanorods photoelectrode for enhanced photocathodic protection of Q235 carbon steel

TiO2 nanotubes have been synthesized by the electrochemical anodizing method in this work. Cobalt and iron have then been deposited on the surface of the prepared nanotubes by chemical bath deposition method. The nanostructures thus prepared have been applied as photoanodes in photoelectrochemical (PEC) water splitting to produce hydrogen. The morphology and phase structure of the synthetic samples have been investigated by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and Raman spectroscopy. The optical properties of the samples have been studied using UV–Vis diffuse reflection spectroscopy (UV–Vis DRS). The impact of cobalt and iron ratios on photocatalytic behavior of the synthetic photoelectrodes has been investigated in the photoelectrochemical water splitting process. The highest photocatalytic activity has been shown by sample T3. Furthermore, great photochemical stability was shown by sample T3 even after four runs in the photocatalytic test. Low price, high activity under illumination, ease of preparation and high stability are some of the advantages of these photoanodes.

Mina Mahvari

Papers

Photoelectrochemical properties of iron-cobalt WTiO2 nanotube photoanodes for water splitting and photocathodic protection of stainless steel

Study of photoelectrochemical water splitting using films based on deposited TiO 2 nanotubes