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Publikation Organic photovoltaics: Potential fate and effects in the environment(Elsevier, 2012) Zimmermann, Yannick-Serge; Schäffer, Andreas; Hugi, Christoph; Fent, Karl; Corvini, Philippe; Lenz, MarkusIn times of dwindling fossil fuels it is particularly crucial to develop novel “green” technologies in order to cover the increasing worldwide demand for energy. Organic photovoltaic solar cells (OPVs) are promising as a renewable energy source due to low energy requirement for production, low resource extraction, and no emission of greenhouse gasses during use. In contrast to silicium-based solar cells, OPVs offer the advantages of light-weight, semi-transparency and mechanical flexibility. As to a possible forthcoming large-scale production, the environmental impact of such OPVs should be assessed and compared to currently best available technologies. For the first time, this review compiles the existing knowledge and identifies gaps regarding the environmental impact of such OPVs in a systematic manner. In this regard, we discuss the components of a typical OPV layer by layer. We discuss the probability of enhanced release of OPV-borne components into the environment during use-phase (e.g. UV- and biodegradation) and end-of-life phase (e.g. incineration and waste disposal). For this purpose, we compiled available data on bioavailability, bioaccumulation, biodegradation, and ecotoxicity. Whereas considerable research has already been carried out concerning the ecotoxicity of certain OPV components (e.g. nanoparticles and fullerenes), others have not been investigated at all so far. In conclusion, there is a general lack of information about fate, behavior as well as potential ecotoxicity of most of the main OPV components and their degradation/transformation products. So far, there is no evidence for a worrying threat coming from OPVs, but since at present, no policy and procedures regarding recycling of OPVs are in action, in particular improper disposal upon end-of-life might result in an adverse effect of OPVs in the environment when applied in large-scale.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Circularity and environmental sustainability of organic and printed electronics(Jenny Stanford Publishing, 2024) Le Blévennec, Kévin; Hengevoss, Dirk; Zimmermann, Yannick-Serge; Brun, Nadja; Hugi, Christoph; Lenz, Markus; Corvini, Philippe; Fent, Karl; Nisato, Giovanni; Lupo, Donald; Rudolf, SimoneIn this chapter, the possible role and impact of organic and printed electronics (OPE) in a transition toward a circular economy and more sustainable society will be discussed. The learning targets are twofold: first, understanding main environmental issues associated with the emerging field of OPE, and second, identifying, through a systemic perspective, the enabling potential of these technologies.04A - Beitrag SammelbandPublikation Methodological approaches for fractionation and speciation to estimate trace element bioavailability in engineered anaerobic digestion ecosystems: An overview(Taylor & Francis, 16.09.2016) van Hullebusch, Eric D.; Guibaud, Gilles; Simon, Stéphane; Lenz, Markus; Yekta, Sepehr Shakeri; Fermoso, Fernando G.; Jain, Rohan; Duester, Lars; Roussel, Jimmy; Guillon, Emmanuel; Skyllberg, Ulf; Almeida, C. Marisa R.; Pechaud, Yoan; Garuti, Mirco; Frunzo, Luigi; Esposito, Giovanni; Carliell-Marquet, Cynthia; Ortner, Markus; Collins, Gavin01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Crystallographic, optical, and electronic properties of the Cs2AgBi1–xInxBr6 double perovskite. Understanding the fundamental photovoltaic efficiency challenges(American Chemical Society, 19.02.2021) Lenz, Markus; Schade, Laura; Mahesh, Suhas; Volonakis, George; Zacharias, Marios; Wenger, Bernard; Schmidt, Felix; Kesava, Sameer Vajjala; Prabhakaran, Dharmalingam; Abdi-Jalebi, Mojtaba; Longo, Giulia; Radaelli, Paolo; Snaith, Henry; Giustino, FelicianoWe present a crystallographic and optoelectronic study of the double perovskite Cs2AgBi1–xInxBr6. From structural characterization we determine that the indium cation shrinks the lattice and shifts the cubic-to-tetragonal phase transition point to lower temperatures. The absorption onset is shifted to shorter wavelengths upon increasing the indium content, leading to wider band gaps, which we rationalize through first-principles band structure calculations. Despite the unfavorable band gap shift, we observe an enhancement in the steady-state photoluminescence intensity, and n-i-p photovoltaic devices present short-circuit current greater than that of neat Cs2AgBiBr6 devices. In order to evaluate the prospects of this material as a solar absorber, we combine accurate absorption measurements with thermodynamic modeling and identify the fundamental limitations of this system. Provided radiative efficiency can be increased and the choice of charge extraction layers are specifically improved, this material could prove to be a useful wide band gap solar absorber.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Characterization of heavy metal toxicity in some plants and microorganisms—A preliminary approach for environmental bioremediation(Elsevier, 13.01.2020) Diaconu, Mariana; Corvini, Philippe; Lenz, Markus01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Low-Temperature Reactive Aerosol Processing for Large-Scale Synthesis of Selenium Nanoparticles(American Chemical Society, 22.08.2020) Viacava, Karen; Ammann, Erik; Lenz, MarkusSelenium nanoparticles (SeNPs) have been suggested for various applications such as food, animal feed, and biomedicine. However, thus far, wet chemical synthesis cannot produce sufficient quantities of SeNPs at the required quality. In this study, reactive aerosol processing is employed to produce SeNPs as powder concentrates of 2.2 to 4.0% (dry weight basis) on the scale of hundreds of kilograms. Citric acid is the most efficient organic precursor (92.5% SeNPs), but polydisperse particles are obtained, and some unknown dissolved Se species are present in the final product. Glycine is less efficient (82.2% SeNPs); however, monodisperse nanoparticles (153 nm; D90 = 215 nm) are obtained, with selenite being the only residue in the final product. The obtained particles consisted of X-ray amorphous (i.e., not diffracting) Se, since no elemental Se allotrope or other solid Se phases were indicated in X-ray diffraction. Reactive aerosol processing involves a limited number of preparation steps (i.e., dissolution and atomization), uses only food-/feed-approved ingredients (selenite, citric acid, glycine) and allows continuous operation and zero waste generation. This makes reactive aerosol processing ideal for the large-scale production of SeNPs.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Bioleaching and toxicity of metallurgical wastes(Elsevier, 09.09.2020) Potysz, Anna; Lenz, Markus; Hedwig, SebastianMetallurgical wastes contain metals that are unrecovered during industrial processing. The disposal of these wastes is technically difficult due to the potential release of metals through weathering. Therefore, alternative management methods are currently sought. The high leaching susceptibility of these wastes combined with the need for alternative sources of rare and critical metals creates a need for residual element recovery. This study evaluated the leaching potential of lead matte and copper slag through chemical mineral acid leaching as well as indirect bioleaching with organic acids and direct bioleaching using Acidithiobacillus thiooxidans. The leaching efficiency of these acids was compared based on different normality equivalents. Additionally, the effects of pulp density (1–10%) and extraction time (24–48 h) were assessed. Slag toxicity was assessed with a germination test in concentrated and diluted leachates using Brassica juncea. The results demonstrated that copper slag is particularly suitable for chemical treatment because as much as 91 wt.% Cu and 85 wt.% Zn or 70 wt.% Cu and 81 wt.% Zn were extracted using HNO3 or bacterial leaching, respectively. The residual slag was characterized by significant metal depletion and the presence of gypsum, rendering it more suitable for further use or disposal. Lead matte released 65 wt.% Cu and 8 wt.% Zn using mineral acid leaching while 70 wt.% Cu and 12 wt.% Zn were released using bacterial leaching. Further process optimization is needed for lead matte to generate residue depletion in toxic metals. Toxicity assessment showed toxic characteristics in metal-loaded leachates originating from waste treatment that inhibited germination rates and root development.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Deterioration of sandstones: Insights from experimental weathering in acidic, neutral and biotic solutions with Acidithiobacillus thiooxidans(Elsevier, 24.02.2020) Potysz, Anna; Schmidt, Felix; Lenz, Markus; Bartz, Wojciech; Zboińska, KatarzynaThe susceptibility of sandstones to deteriorative factors when used for construction requires detailed experimental evaluation. This study investigated the (bio)weathering behaviour of Lower-Silesian Cretaceous sandstones (quartz arenites) to quantify the deteriorative effect of bacterium Acidithiobacillus thiooxidans. For controls, ultrapure water (in undersaturated conditions) and sterile acidic medium (in abiotic acidic conditions pH 2.5) were used. Sandstone exposure to A. thiooxidans mimicked the extremely acidic conditions (pH up to 0.9) that may develop under long-term weathering, which promote microbial activity and acidic metabolite production. Element release was assessed using triple quadrupole inductively coupled plasma mass spectrometry (QQQ-ICP-MS) and identifying potential element donor minerals through scanning electron microscopy, coupled with energy dispersive spectrometer (SEM-EDS). The results demonstrated that sandstones were relatively susceptible to weathering, especially when exposed to aggressive acidic conditions, where the presence of bacteria apparently acts as an accelerating factor in deterioration. Based on Si release, sandstone degradation under biotic conditions was 0.27% within 86 days, whereas the dissolution achieved in ultrapure water did not exceed 0.02%. A highly pronounced weathering feature observed on sandstones was the dissolution of goethite and/or kaolinite cement, whereas quartz was less susceptible to weathering under the conditions studied. Bioweathering investigations may help solve deterioration issues in sandstone building materials.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Biodeterioration affecting efficiency and lifetime of plastic-based photovoltaics(Elsevier, 16.09.2020) Schmidt, Felix; Lenz, Markus; Schaeffer, Andreas; Zimmermann, Yannick; Alves dos Reis Benatto, Gisele; Kolvenbach, Boris; Krebs, FrederikThe low environmental impact of electricity generation using solar cells crucially depends on high energy-conversion efficiencies, long lifetimes and a minimal energy and material demand during production. Emerging thin-film photovoltaics such as perovskites on plastic substrates could hold promise to fulfil all these requirements. Under real-world operating conditions photovoltaic operation is challenged by biological stressors, which have not been incorporated for evaluation in any test. Such stressors cause biodeterioration, which impairs diverse, apparently inert materials such as rock, glass and steel and therefore could significantly affect the function and stability of plastic-based solar cells. Given that different photovoltaic technologies commonly use similar materials, the biodeterioration mechanisms reviewed here may possibly affect the efficiency and lifetimes of several technologies, if they occur sufficiently fast (during the expected lifetime of photovoltaics). Once the physical integrity of uppermost module layers is challenged by biofilm growth microbially mediated dissolution and precipitation reactions of photovoltaic functional materials are very likely to occur. The biodeterioration of substrates and seals also represents emission points for the release of potentially harmful photovoltaic constituents to the environment01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Renewable Energy from Finite Resources: Example of Emerging Photovoltaics(Schweizerische Chemische Gesellschaft, 01.11.2019) Schmidt, Felix; Lenz, MarkusRenewable energies, such as sunlight, wind and geothermal heat, are resources that are replaced rapidly by natural processes. However, wind, hydro and solar installations strictly require raw materials that are, in fact, not renewable. Many raw materials are already facing a supply shortage which cannot be easily overcome. This work reviews the problem of critical raw material (CRM) use in photovoltaics (PV) as an example and explains why supply cannot be easily increased to meet demand. We discuss whether there is indeed a 'struggle for elements' in a Darwinian sense, which ultimately leads to a 'survival of the fittest' race in renewable energy technology. In the case of PV, the perception of the definition of 'fittest' needs to change from that considering energy conversion efficiency alone to that which holistically considers net energy produced per emission under the premise that sufficient environmentally and socially acceptable raw material supply exists for renewable energies and all other sectors.01A - Beitrag in wissenschaftlicher Zeitschrift