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In this dissertation, hydroxyapatite-based and hydroxyapatite with carbon composite materials have been rationally designed, synthesized, characterized and applied to processes of environmental concern, namely wastewater remediation (as sorbents) and electrochemical CO2 reduction reaction, CO2RR (as electrocatalysts). Pristine hydroxyapatite (HAP, Ca10(PO4)6(OH)2) and composite HAP/carbon materials have been synthesized according to a simple wet co-precipitation route. Composition, structure and morphology of samples have been investigated by a plethora of physical-chemical techniques (i.e. ICP/OES elemental analyses, N2 adsorption/desorption isotherms, XRD, TEM (and STEM) imaging, TEM/EDX mapping, transmittance FT-IR and Raman spectroscopies, and XPS). Since adsorption onto materials? surface is crucial in both sorption and catalytic applications, a special attention has been devoted to surface properties, determined by means of zeta potential measurements, gas-solid calorimetric/volumetric titrations, and liquid-solid volumetric titrations, thus assessing the amphoteric nature of HAP-based surfaces. At first, pristine pristine HAP has been studied as sorbent for the remediation of inorganic pollution in wastewater (i.e. heavy metal cations such as Cu(II), Pb(II), Cr(III), Ni(II) and Co(II)). Stirred batch adsorption tests and collection of adsorption isotherms in solutions containing both individual and mixtures of heavy metal cations allowed to quantitatively assess HAP sorption ability. Ad-hoc experiments (i.e. microcalorimetric adsorption isotherms) and physical-chemical investigation of metal-loaded samples shed light on the adsorption mechanisms of several polluting species onto HAP surface. Eco-friendly HAP/carbon composites from renewable resources have been instead applied to the remediation of more complex effluents, where simultaneous organic and inorganic pollution may occur. Thanks to their dual nature, HAP/carbon composites exerted outstanding adsorption performances towards both class of polluting species. Both in the form of pristine HAP and HAP/carbon composites, the sorbents exhibited a strict retention of adsorbed pollutants when undergoing leach testing, therefore ensuring no secondary pollution issues. In an exploratory study, HAP/carbon composites have been also implemented as modifiers in self-standing and mechanically stable electrodes for the electrochemical detection of heavy metal cations traces in waterbodies. Benefitting from the pronounced HAP affinity towards such species, encouraging results have been obtained on the detection of some benchmark pollutants, although the registered limits of detection (ca. one order of magnitude improvement to match legislative requirements) and linearity ranges currently limit HAP/carbon modified electrodes applications. Finally, during a 6-months stay at University of California Irvine (UCI), hosted by Prof. Plamen Atanassov group, HAP has been applied as dopant in CO2RR electrocatalysts. The peculiar ability of HAP amphoteric surface to adsorb and destabilize CO2 (i.e. breakage of its linearity) has been exploited in composite electrocatalysts, composed by copper nanoparticles (active phase) and HAP (dopant), supported on N-doped 3D assembly of graphene nanosheets (3D-GNS, carbonaceous support). When tested in a lab scale CO2 electrolyzer, HAP-doped electrocatalysts displayed a faradic efficiency (FE) towards CO2RR ? 80% throughout the whole potential range under investigation, minimizing parasitic Hydrogen Evolution Reaction (HER). Interestingly, HAP doping actually altered CO2RR product distribution: in particular, small quantities of C2+ products were produced under low applied overpotential while at higher voltage formate production was boosted. Product distribution alteration has been rationalized taking into account the ability of HAP acid-basic surface groups to stabilize CO2 reduction intermediate species, directing the the selectivity of electrochemical CO2RR processes. Overall, the present study demonstrates that the unique features of HAP make it a versatile material which may be applied for the protection of the environment at 360 degrees, from water to air remediation, as pristine and/or composite material, as sorbent and/or catalysts? dopant.

EOPEN (https://eopen-project.eu/) is a project which has received funding from the European Union’s Horizon 2020 research and innovation programme under the topic EO Big Data Shift in 2017 and has a duration of 3 years, starting from November 2017. In this work, we present the concept of the project, its objectives and the lessons learnt after almost one year of project lifetime, as a follow-up to our previous project presentation at ESA BiDS’17 in Toulouse, France.

Flood detection using satellite data Data fusion and integration of non-EO data technologies within the H2020-EOPEN project Future directions in Emergency Management and Early Warning Services that combine EO with non -EO data

The overall objective of EOPEN is to provide a platform targeting non-expert EO data users (non-traditional user communities), experts and the SME community that reveals and makes Copernicus data and services easy to use for Big Data applications by providing EO data analytics services, decision making and infrastructure to support the Big Data processing life-cycle allowing the chaining of value adding activities across multiple platforms.

We collect Twitter posts to monitor flood events in Italy during a period of one year. We analyse the statistics of the collected content. We extract word clouds, popular keywords and we demonstrate events in a one-year timeline. A large part of the collection has been annotated by Italian experts on the relevance or not to flood events.

The WeSenseIt project defines citizen observatories as “A method, an environment and an infrastructure supporting an information ecosystem for communities and citizens, as well as emergency operators and policymakers, for discussion, monitoring and intervention on situations, places and events” . A collaborative approach has been taken to develop solutions that involve an exchange of information and expertise from all participants and where the focus is on arriving at practical solutions with a clear vision and direction. This has created a shared ownership scheme, and shifts power to the process itself rather than remaining within authorities, developers or decision-makers. The project’s emphasis is on delivering highly innovative technologies to support citizens, communities and authorities in developing a real-time situation awareness while ensuring all stakeholders play their part. Implementation has been through a combination of crowdsourcing, custom applications and dedicated web portals designed to foster collaboration, and which has created a shared knowledge base that facilitates decision-making processes and engages with communities. Data is captured via innovative sensors that are used directly by citizens, crowdsourcing from social networks (or by collective intelligence).