Solar Photocatalytic Degradation of Trace Organic Pollutants in Water by Bi(0)-Doped Bismuth Oxyhalide Thin Films

Anirban Dandapat; Inna Horovitz; Hani Gnayem; Yoel Sasson; Dror Avisar; Thomas Luxbacher; Hadas Mamane

doi:10.1021/acsomega.8b00759

Solar Photocatalytic Degradation of Trace Organic Pollutants in Water by Bi(0)-Doped Bismuth Oxyhalide Thin Films

ACS Omega. 2018 Sep 7;3(9):10858-10865. doi: 10.1021/acsomega.8b00759. eCollection 2018 Sep 30.

Authors

Anirban Dandapat¹, Inna Horovitz^{2

2}, Hani Gnayem³, Yoel Sasson³, Dror Avisar², Thomas Luxbacher⁴, Hadas Mamane²

Affiliations

¹ Department of Biotechnology, Bhimtal Campus, Kumaun University, Nainital, Uttarakhand 263136, India.
² School of Mechanical Engineering, Faculty of Engineering, and The Water Research Center, School of Earth Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
³ Casali Center of Applied Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
⁴ Anton Paar GmbH, Anton-Paar-Street 20, 8054 Graz, Austria.

Abstract

Herein, we demonstrate the fabrication of Bi(0)-doped bismuth oxyhalide solid solution films for the removal of trace organic pollutants (TrOPs) in water. With the advantage of a viscous AlOOH sol, very high loadings (75 wt %) of bismuth oxyhalides were embedded within the thin films and calcined at 500 °C to develop porous alumina composite coatings. Various concentrations of Bi(0) doping were tested for their photocatalytic activity. Seven TrOPs including iopromide (IPRM), iohexol (IHX), iopamidol (IPMD), sulfamethoxazole (SMX), carbamazepine, venlafaxine, and bezafibrate (BZF) were selected for this study based on their occurrence and detection in effluents and surface waters worldwide. In all tests, with the exception of IPRM, 3% Bi(0)-doped BiOCl_0.875Br_0.125 showed highest activity, which can be attributed to its unique, highly organized, and compact morphology besides its well-matched energy band positions. Although IPMD, IHX, IPRM, and SMX are susceptible to photolysis, still the photocatalytic activity significantly augmented the removal of all tested compounds. In addition, analysis of the surface charge excluded electrostatic interactions and confirmed the ion-exchange adsorption mechanism for the high degradation rate of BZF in the presence of bismuth oxyhalides.