Measuring and predicting soil nitrogen with point-of-use sensors and machine learning

for Short Presentation SYNTHESIS AND APPLICATION STUDY OF Fe3O4/GRAPHENE HYBRID FOR WATER REMEDIATION J. Oliveras*, Neus G. Bastús, Víctor Puntes 1 Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Catalonia, Spain. 2 Universitat Autònoma de Barcelona (UAB), Campus UAB, 08193, Bellaterra, Barcelona, Catalonia, Spain. 3 ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Catalonia, Spain. 4 Vall d’Hebron Institut de Recerca (VHIR), 08035, Barcelona, Catalonia, Spain. (*) jana.oliveras@icn2.cat In a world where 1.2 billion people have no access to clean water, emerging pollutants (care products, pesticides, drugs, and their metabolites) found in drinking water have recently been of great concern. Up to now, over 200 pharmacs have been detected in freshwaters, the most commonly found are antibiotics followed by painkillers, analgesics and antidepressants, which can affect plants and animal’s life including human beings. These compounds are usually excreted nonmetabolised by humans and livestock, directly to wastewater in the first case and also in sludge later used as fertiliser in the latter case. The existence of pharmaceuticals in drinking water is a potential threat for life of unknown outcome. Although the reported environmental concentrations of nonsteroidal anti-inflammatory drugs (NSAIDs) are lower than those that may threaten ecosystems, they tend to increase due to their wide usage and irresponsible disposal and still can impact aquatic ecosystems causing chronic harm, evidence showing mixtures of these agents to allow individual pollutants to be more harmful at lower concentrations. Among them, Ibuprofen (IBP) and Diclofenac (DCF) are considered Class I pharmaceuticals which must be dealt with in urgency while estimated to be consumed in several kilotons per year globally. In this work a graphene-based magnetic hybrid material decorated with Fe3O4 nanocrystals (NCs) is designed for effective removal of emerging pollutants when they are present at low concentrations. A green preparation of this hybrid, a study of its application and performance and a simple, direct method of detection and quantification by UV-Vis are presented in the following pages. Several variations of the Fe3O4/Graphene hybrid were fabricated such as Fe3O4/Graphene oxide and a multimodal Fe3O4-TiO2/Graphene hybrid which explored the photocatalytical degradation of the captured drugs.