The photoelectrochemical behavior of nanostructured TiO 2 (consisting mainly of anatase) films, with thicknesses ranging from ca. 0.6 to 45 µm, was examined under the band gap UV illumination. The shape of the spectral photoresponses exhibiting a maximum at 300 nm, irrespective the film thickness, and the excellent photocurrent-voltage characteristics of the thickest films are inconsistent with the previously proposed models aimed at describing electron transport in such nanoporous semiconductor networks. It was found that even electrophoretically deposited nanoparticulate films, simply dried at room temperature, behaved essentially as the high-temperature-annealed films. An explanation of the particular behavior of the nanostructured anatase films, in terms of the self-doping occurring at the initial stages of the photocurrent flow, is proposed. This initial film charging causes an insulator-metal (Mott) transition in a donor band of anatase, accompanied by a sharp rise in conductivity of the nanoparticles. Such a self-doping appears as a special feature of nanostructured semiconductor films filled with the electrolyte and characterized by large surface-area-tovolume ratios. This offers a convenient way of compensating the excess charge within the semiconductor by the adjustment of the ion concentration in the Helmholtz layer.

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The Bellecombe pilot site – SIPIBEL – was created in 2010 in order to study the characterisation, treatability and impacts of hospital effluents in an urban wastewater treatment plant. This pilot site is composed of: i) the Alpes Léman hospital (CHAL), opened in February 2012, ii) the Bellecombe wastewater treatment plant, with two separate treatment lines allowing to fully separate the hospital wastewater and the urban wastewater, and iii) the Arve River as the receiving water body and a tributary of the Rhône River and the Geneva aquifer. The database includes in total 48 439 values measured on 961 samples (raw and treated hospital and urban wastewater, activated sludge in aeration tanks, dried sludge after dewatering, river and groundwater, and a few additional campaigns in aerobic and anaerobic sewers) with 44 455 physico-chemistry values (including 15 pharmaceuticals and 14 related transformation products, biocides compounds, metals, organic micropollutants), 2 193 bioassay values (ecotoxicity), 1 679 microbiology values (including microorganisms and antibioresistance indicators) and 112 hydrobiology values.