Photoelectrocatalytic oxidation of phenol for water treatment using a BiVO 4 thin-film photoanode
- PDF / 891,936 Bytes
- 13 Pages / 584.957 x 782.986 pts Page_size
- 18 Downloads / 172 Views
Paula Perez-Rodriguez and Mathew J. Alani Photovoltaic Materials and Devices, Department of Electrical Sustainable Energy, Faculty of Electrical Engineering, Mathematics and Computer Science, 2628 CD Delft, The Netherlands
Wilson A. Smith Materials for Energy Storage and Conversion (MECS) group, Department of Chemical Engineering, Faculty of Applied Sciences, 2628 BL Delft, The Netherlands
Luuk C. Rietveld Drinking Water, Department of Sanitary Engineering, Faculty of Civil Engineering and Geosciences, 2628 CN Delft, The Netherlands
Miro Zeman and Arno H.M. Smets Photovoltaic Materials and Devices, Department of Electrical Sustainable Energy, Faculty of Electrical Engineering, Mathematics and Computer Science, 2628 CD Delft, The Netherlands (Received 17 April 2016; accepted 27 July 2016)
The removal of organics by photoelectrocatalytic oxidation offers a viable option to remove the contaminants at low concentrations. In this paper, we propose a BiVO4 thin films synthesized via spray pyrolysis for photoelectrocatalyic oxidation of phenol with solar light. We compare the properties of BiVO4 with those of the commonly used photocatalyst TiO2. In addition, BiVO4 films with W gradient doping were fabricated and tested for improving the photocatalytic performance of BiVO4. X-ray diffraction, atomic force microscopy, incident photon to current efficiency and spectrophotometry have been conducted for BiVO4 films of different thicknesses, as well as for TiO2. The electrochemical impedance spectroscopy and dark conductivity measurements were conducted. Phenol removal has been measured for both the TiO2 and BiVO4 samples. The best performance was found to be for a 300 nm undoped BiVO4 film, being able to reduce the phenol concentration up to 30.0% of the initial concentration in four hours.
I. INTRODUCTION
Access to clean water is, along with energy and food, one of the most important challenges that our society will face in the near and long term future. The degradation of many organic pollutants in water can be accomplished either by biological, physical, or chemical means. The biological oxidation of pollutants is considered economically favorable, but many toxic compounds cannot be degraded by this method.1 Physical methods such as filtration by membranes or adsorption are also widely used.2,3 However, in most cases these methods do not destroy the pollutants but only transfer them from one phase to another. Finally, chemical methods for water treatment offer a flexible and safe alternative to remove a wide variety of pollutants.4 In particular, photocatalytic
Contributing Editor: Xiaobo Chen a) Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2016.290
treatments are able to remove toxic organic compounds, including ecologically hazardous cyanides and other residual compounds, even at low concentrations, making this approach very suitable for the last stages of water purification.5 In addition, sunlight which is used to drive the chemical reaction has the potential to reduce the
Data Loading...
