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Water contamination with the enteroprotozoan parasite Cryptosporidium is a current challenge worldwide. Solar water disinfection (SODIS) has been proved as a potential alternative for its inactivation, especially at household level in low-income environments. This work presents the first comprehensive kinetic model for the inactivation of Cryptosporidium parvum oocysts by sunlight that, based on the mechanism of the process, is able to describe not only the individual thermal and spectral actions but also their synergy. Model predictions are capable of estimating the required solar exposure to achieve the desired level of disinfection under variable solar spectral irradiance and environmental temperature conditions for different locations worldwide. The thermal contribution can be successfully described by a modified Arrhenius equation while photoinactivation is based on a series-event mechanistic model. The wavelength-dependent spectral effect is modeled by means of the estimation of the C. parvum extinction coefficients and the determination of the quantum yield of the inactivation process. Model predictions show a 3.7% error with respect to experimental results carried out under a wide range of temperature (30 to 45 °C) and UV irradiance (0 to 50 W·m−2). Furthermore, the model was validated in three scenarios in which the spectral distribution radiation was modified using different plastic materials common in SODIS devices, ensuring accurate forecasting of inactivation rates for real conditions ; The authors gratefully acknowledge the financial support of the European Union's Horizon 2020 research and innovation program under WATERSPOUTT H2020-Water-5c-2015 project (GA 688928) and under PANIWATER project (GA 820718), jointly funded by the European Commission and the Department of Science and Technology of India (DST). Ángela García Gil also acknowledges Técnicas Reunidas for the economic support to finance her scholarship in Residencia de Estudiantes and Spanish Ministry of Education for her FPU grant ...

Developing highly efficient photocatalysts for artificial photosynthesis is one of the grand challenges in solar energy conversion. Among advanced photoactive materials, conjugated porous polymers (CPPs) possess a powerful combination of high surface areas, intrinsic porosity, cross-linked nature, and fully π-conjugated electronic systems. Here, based on these fascinating properties, organic–inorganic hybrid heterostructures composed of CPPs and TiO2 for the photocatalytic CO2 reduction and H2 evolution from water are developed. The study is focused on CPPs based on the boron dipyrromethene (BODIPY) and boron pyrrol hydrazine (BOPHY) families of compounds. It is shown that hybrid photocatalysts are active for the conversion of CO2 mainly into CH4 and CO, with CH4 production 4 times over the benchmark TiO2. Hydrogen evolution from water surpassed by 37.9-times that of TiO2, reaching 200 mmol gcat−1 and photonic efficiency of 20.4% in the presence of Pt co-catalyst (1 wt% Pt). Advanced photophysical studies, based on time-resolved photoluminescence and transient absorption spectroscopy, reveal the creation of a type II heterojunction in the hybrids. The unique interfacial interaction between CPPs and TiO2 results in longer carriers' lifetimes and a higher driving force for electron transfer, opening the door to a new generation of photocatalysts for artificial photosynthesis. ; This work received funding from the European Union's Horizon 2020 research and innovation program under European Research Council (ERC) through the HyMAP project (grant agreement No. 648319) as well as the Marie Skłodowska-Curie grant agreement No 754382. Financial support was received from AEI-MICINN/FEDER, UE through the Nympha Project (PID2019-106315RB-I00), the regional government of "Comunidad de Madrid" and the European Structural Funds through their financial support to FotoArt-CM project (S2018/NMT-4367). Besides, Fundación Ramon Areces funded this work through the ArtLeaf project. L.C. acknowledges the European Union's Horizon 2020 ...