0000000000069756
AUTHOR
Raphaël Schneider
Heterostructured metal oxides-ZnO nanorods films prepared by SPPS route for photodegradation applications
Abstract This work presents the first preparation using the Solution Precursor Plasma Spray process of heterostructured films associating ZnO nanorods (NRs) and various metal oxides (CuO, Fe2O3 and Co3O4) by Solution Precursor Plasma Spray process. These CuO/ZnO, Fe2O3/ZnO and Co3O4/ZnO films exhibit hierarchically chocolate sticks-like, dandelion-like or chrysanthemum-like surface morphologies. These heterostructures were confirmed by SEM, XRD, EDS and Raman analyses. The bandgaps of heterostructured films are narrower than that of pure ZnO. The CuO/ZnO film exhibits the highest photocatalytic activity both under UV and visible light irradiation for the degradation of the Orange II dye due…
Influence of laminated architectures of heterostructured CeO2-ZnO and Fe2O3-ZnO films on photodegradation performances
Abstract The development of photocatalytically active films has gained a great attention in recent years. Herein, new heterostructured films associating ZnO and CeO2 or Fe2O3 and exhibiting various architectures were prepared by the solution precursor thermal spray (SPPS) process. The paper examines the effect of the films laminated architectures on the photodegradation performance. For CeO2-ZnO and Fe2O3-ZnO films, the photodegradation efficiency of the Orange II dye is 100% and 95% after 240 min UV light irradiation and after 360 min visible light irradiation, respectively. The photocatalytic activity of the laminated structures was found to depend on the materials used to construct the h…
Tunable morphologies of ZnO films via the solution precursor plasma spray process for improved photocatalytic degradation performance
Abstract The Solution Precursor Plasma Spray (SPPS) process is a novel, versatile and one-step route for building photocatalytic films. Herein, the influence of the precursor solution composition on the microstructure and on the properties of ZnO films prepared via the SPPS process was studied. Nanostructured ZnO particles (i.e. nanorods (NRs) and nanowires (NWs)) were obtained by using a solution of pure Zn(OAc)2 rather than pure Zn(NO3)2. Upon adding urea to the Zn(NO3)2 solution, NRs structured ZnO films were formed as well. The addition of acetic acid into the Zn(OAc)2 solution led to a damage of the nanostructured morphologies likely due to the inhibition of the zinc-containing cluster…
Development of photocatalytically active heterostructured MnO/ZnO and CuO/ZnO films via solution precursor plasma spray process
Abstract Heterostructured ZnO photocatalysts for the degradation of organic pollutant are mainly synthesized by conventional chemical methods, suffering from long duration, multi-steps, and post-treatment of the powder-formed catalysts after usage. In this paper, Solution Precursor Plasma Spray (SPPS) process is demonstrated to be a fast and efficient method for the one-step preparation of MnO/ZnO and CuO/ZnO heterostructured films for photocatalytic applications. The ratios between MnO or CuO and ZnO materials in the films were easily adjusted by varying the molar ratio of Mn(OAc)2 or Cu(OAc)2 relative to Zn(OAc)2 during the SPPS synthesis. To optimize the microstructure of selected CuO/Zn…
Solution precursor plasma spray process as an alternative rapid one-step route for the development of hierarchical ZnO films for improved photocatalytic degradation
Abstract The development of efficient photocatalytic hierarchical coral-like ZnO films via a relatively simple, efficient, rapid and single-step process is essential for industrial development. Herein, we report a novel method for directly synthesizing well-shaped ZnO nanorods (NRs) by Solution Precursor Plasma Spray (SPPS) process rather than conventional spherical/ellipsoidal particles. In the prepared ZnO-NRs films, the ZnO NRs display an average diameter of 190 nm, and exhibit a preferential orientation growth along (002) plane compared to a reference ZnO films (called ZnO-P) containing spherical/ellipsoidal particles. ZnO-NRs films exhibit relative narrower bandgap (3.02 eV) probably d…
One-step synthesis and deposition of ZnFe2O4 related composite films via SPPS route for photodegradation application
Binary spinel-type metal oxides (AB2O4) related materials, including ferrites (AFe2O4), are attractive photocatalysts thanks to their excellent visible light response for the photodegradation of organic pollutants. Currently, these materials are synthesized via conventional chemical routes suffering from long preparation duration and multistep. Moreover, the photocatalysts are obtained as nano-powders from conventional chemical routes would introduce another drawback for their recycling and reuse. From an industrial perspective, it is desirable to develop an efficient and facile synthesis process to produce photocatalysts in a non-dispersible form. Herein, we demonstrate that the solution p…
Oxygen-defective ZnO films with various nanostructures prepared via a rapid one-step process and corresponding photocatalytic degradation applications.
Abstract The deposition of oxygen-defective ZnO films exhibiting varied nanostructures via Solution Precursor Plasma Spray (SPPS) route, a one-step, minute-scaled duration and large scale method, is reported. The in situ formation of oxygen vacancies in ZnO films was confirmed by UV–Visible, Raman and photoluminescence (PL) spectroscopy and the as-prepared samples exhibit a bandgap as low as 3.02 eV. Density functional theory (DFT) simulation demonstrates that the polarization of ZnO is enhanced by the created oxygen vacancies, leading to substantially improved photocatalytic activity. The comparative experiments also revealed that forming and preserving appropriate ZnO precursor clusters i…