Optical and self-cleaning properties of titanium, tungsten and go composite films
A recent study discussed the optical and self-cleaning properties of titanium, tungsten and go composite films, This paper, published in the journal Surface and Interface, explores the optical properties of photocatalytic titanium dioxide - tungsten trioxide - reduced graphene oxide (TiO2-WO3-RGO) (TWG) and TiO2 films and the feasibility of using these films for different applications, particularly as self-cleaning coatings (SCC).
In recent years, SCCs have received considerable attention in a number of applications in solar energy conversion systems, the automotive industry and the construction sector. In addition to self-cleaning performance, multi-functional self-cleaning coating also shows antibacterial activity and anti-fouling, anti-fog, anti-frost performance.
Short-chain chloride on pv modules reduces fouling and results in improved power output by significantly preventing efficiency losses during the first 15 years of pv module operation. However, these coatings can degrade over time due to exposure to weathering, which requires recoating the components.
A good SCC must have a high photodegradation efficiency of organic pollutants and superhydrophobicity or superhydrophilicity to wash away the by-products of the photocatalytic process. These requirements can be controlled by the morphology and structure of the photocatalyst (PC).
Ordinary PCS, such as zinc oxide, titanium dioxide and silicon dioxide, are not suitable for SCC due to the large band gap value requiring ultraviolet (UV) activation. In one study, the researchers investigated the optical properties of 450, 300, and 150 nanometer-thick TiO2 films deposited by chemical vapor deposition.
These films show a maximum transmittance of 78.2% at 100 nm thickness and visible light transmittance of up to 78% at 150 nm thickness. The absorption coefficient increases with the decrease of thickness, while the refractive index increases with the increase of film thickness. However, a high band gap value of 3.69eV was observed in films with a thickness of 150 nm. Only when the thickness is increased to 450 nm does the band gap of the film decrease.
Composites with carbon derivative fillers, such as reduced graphene oxide (rGO) and metal oxide matrix, can be activated by visible light (VIS) and also become effective PC materials due to the increased surface area of carbon fillers. An enhanced electronic storage material was obtained by adding rGO into tio2-WO3 composite by one-step hydrothermal method. A photocatalyst for the degradation of 2, 4-dichlorophenoxyacetic acid was synthesized by scattering gold doped Tio2-Wo3 nanoparticles (NPs) on rGO.
In the recently published in the journal surface and interface of a study, the researchers synthesized compound photocatalytic titanium dioxide - tungsten trioxide - reduction of graphene oxide film, and to assess the feasibility of it as self-cleaning coating, the film has good light under ultraviolet - visible radiation activity, controllable optical properties and good wetting properties. The researchers used a low-temperature, multifunctional and low-cost deposition method to apply titanium, tungsten and go composite thin film powders to large areas.
Titanium, tungsten and go composite film films deposited by single batch deposition can be effectively used as self-cleaning coatings compared to ordinary photocatalyst films such as tiO2-based films.
